Xamarin Evolve 16 – Conference Day 2

If you want to read the first 3 instalments, go here:

  1. Training Day 1
  2. Training Day 2
  3. Conference Day 1

This blogpost marks the end of Xamarin Evolve 2016 already. Wow, time flies, but this was another great Evolve. I didn’t expect that the same vibe of Evolve 2013 could be recreated but Xamarin has some special fairy dust and made it happen again, only bigger. Much bigger.

Today was a bit of a roller coaster ride for me – and I wasn’t even at the Wizarding World of Harry Potter anymore! But more on that later…

I attended the Xamarin MVP breakfast at 7:00am, bright and early. A nice bunch of people from the MVP community showed up and we got to chat with some of the Xamarin folks about the Microsoft acquisition and the way forward.


The main Evolve event continued with the Day 2 Keynote session with special guest Grant Imahara from Mythbusters. Grant had an inspirational story about his time as a Mythbusters team member, doing all these crazy things for the sake of science (and fun). The way he had to solve problems and challenges has parallels with how we approach software development. It comes down to fostering creativity and using failure as a design tool.

Sessions like these always work great for inspiration.

Breakout sessions

Designing for TouchJosh Clark
I planned on attending the 2 hour ‘Designing for Touch’ seminar by Josh Clark. Josh is an engaging speaker and his presentation covered a lot of great tips about how people hold and operate their mobile devices using Touch.

Depending on the size of the phone, there are roughly three different types of grips: one-handed, cradled grip + 1 finger, the so called “BlackBerry prayer” grip. As it turns out, the thumb is the most important input “device” a user has, so it makes sense to optimize for input and/or manipulation via thumbs.

The preferred placement of controls on Android differs from iOS. Android has a fixed “soft button” navigation bar at the bottom of the screen, and putting controls just above that bar is tricky. On iOS it makes sense to put tab-navigation at the very bottom of the screen. Per platform native UI’s have very specific needs, so if you want to build a quality app, you must keep this in mind.

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Josh put his slides up for download. They’re worth checking out:

Unfortunately I had to leave the second part – just when Josh started to talk about gestures – because I had a special invite for…

Lunch with Woz?!

Wow! I was privileged to join a party of Xamarins and customers in a small lunch setting together with Apple co-founder and inventor of the Apple I and II computers, Steve Wozniak! It was mind blowing to meet and greet such an icon of our industry.

I guess it was overwhelming to most of us because we sat there most of the time just marvelling at his amazing stories. Woz told us that he doesn’t eat lunch, he sticks with just one meal per day, which gave him plenty of room to talk. It was great to hear about his first endeavours in making computer hardware, soldering the circuits for arcade games, his favourite apps and the Apple Watch.

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Three industry legends!

What struck me most was that he has a sincere passion for software development and software developers. He is definitely a tech geek for life and a genuinely nice guy. I got my picture taken with Woz, but I’m still awaiting the pic from the photographer… Exciting!

Xammy and Closing keynote

Xammy AwardsStephanie Schatz
At the end of the day, it was time for the Xammy Awards, an award for outstanding apps built with Xamarin technology. The finalists are listed on the Xamarin Blog. One of them, in the Enterprise App category, was NS / Dutch Railways.

Marco and Patrick from Info Support are members in the team building this app. I worked at Info Support for 16 years and my last project before I left the company for Xpirit was: this very project! I was the solution architect during the startup and first iterations of development of this app and the team did a fantastic job building these apps on top of that architecture. So I was pretty proud when this happened:

Congratulations Marco and team, great job!

Closing panel discussionSteve Wozniak & Miguel de Icaza
Steve Wozniak and Miguel de Icaza joined on stage for a panel discussion about the history and future of apps. The same way as during lunch, Woz passionately told his fantastic stories and shared his vision on where computing might go in the future. Woz believes strongly in personal assistants like Siri and/or Amazon Echo.

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Unfortunately we didn’t get to hear much from Miguel in this session, but Woz was an inspiration. Another thing that stood out was his dedication to educating young children to do programming. In his heart, Woz always stayed an engineer and a teacher.

Closing thoughts

We ended the conference at a closing party over at the Dragonfly restaurant. This was another great location with fantastic Japanese food.

Closing thoughts: Evolve 2016 was a fantastic conference. I’m amazed how Xamarin managed to keep the vibe of the original Evolve in 2013, and just made it bigger and more awesome. All Xamarins were very approachable and close to their community members. I found this in my bedroom after the keynote, for participating in the DevOps panel yesterday:

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It says: Thank You! From Xamarin. I say: Thank YOU, Xamarin! See you next year at Evolve 2017. Let’s make this happen!

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The band of brothers with whom I spent this week.

Still here? What’s that? Food posts? Ok, here are some…

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Time for the Future of Apps!



Xamarin Evolve 16 – Conference Day 1

Day 1 of the Xamarin Evolve 2016 conference is a wrap! It was a full day for me… It started at 6:15am for the Mini-Hack 5k run, organised by Craig Dunn. A bunch of Evolve attendees went for a leisurely run in the area, thereby unlocking the first Evolve Mini-Hack.


After a refreshing shower and some breakfast, it was finally time for the keynote. The one impression I had after this keynote is: Xamarin is on fire! The keynote was huge. A big stage, an enormous screen and 1700+ excited people in the room anticipating what Xamarin would be announcing.

I made a sketch note out of my personal highlights:

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A lot of topics were covered. I want to share the ones that stood out to me:

The Xamarin team has been working hard to release the Xamarin platform and its surrounding frameworks as Open Source Software on Github. This morning it was released to the public. You can find it via open.xamarin.com, or directly on GitHub. This must be a breakthrough moment for Miguel! Congratulations to the whole team for this achievement, and thank you for being such strong believers in OSS.

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It made sense that Xamarin was closed source when it was their bread & butter. But now at Microsoft, with their fresh new attitude towards open source, it’s great to see Xamarin added to that array of OSS products and frameworks.

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Xamarin Studio 6 Release Candidate
The Release Candidate for the latest version of Xamarin Studio is available now in the Beta channel. This is a very nice release, which features a Dark Theme, a complete visual overhaul to fit with the UX guidelines for OS X El Capitan and built-in Roslyn support. I’ve been working with the preview version on and off and it has matured a lot. I really like the new polished look and the more stable code editor thanks to Roslyn. One of the most notable changes is the Broken State Support, so that IntelliSense doesn’t blow up if there’s a syntax error a few lines above.

iOS Simulator for Windows
The new iOS Simulator was already presented briefly in the //build/ keynote by Miguel. However today Miguel showed how pen pressure input on a Surface Pro running the simulator is passed through to the iOS Simulator which runs on a Mac somewhere in the network.

The cross platform UI framework, Xamarin.Forms, is becoming more and more mature. This update brings support for so-called DataPages: a ready built and styled set of views that you can feed Azure Mobile Services data or local storage of JSON data. This is a higher level abstraction that lets you set up data driven pages very quickly, but I’m not sure how suited this is for production scenario’s. There is no MVVM in play – at least not for the developer, maybe behind the scenes – to tweak the behaviour. And you know me when it comes to abstractions… 🙂

A feature I did like *a lot* is the ability to drop in a native UI control directly into a Forms layout hierarchy. It’s called Xamarin.Forms Native Embedding. So you can now add a native Floating Action Button to your Android app without the hassle of writing a Renderer, etc.

And then…

The Xamarin Forms Previewer is a built in player for your Xamarin.Forms markup code that gives you Gorilla Player like direct feedback inside Xamarin Studio while you’re editing your pages. This is so awesome, because it speeds up the development cycle tremendously! Definitely one of my favourite announcements from the keynote and Nina Vyedin did a great job presenting it.

Xamarin Workbooks
Miguel already talked about Xamarin Workbooks at //build/ and he showed us how the tool is progressing. Workbooks is a fantastic tool for teaching and communicating about code. My pal Marco already alluded to this in his blog: it’s a nice visual way to teach children to code for example. I’ve been doing some classes for the Dutch “hour of code” initiative called CodeUur.nl and I’m thinking about using Workbooks as a tool for that. In any case, it’s clear from the keynote that Workbooks is Miguel’s favourite project at the moment. And rightfully so.

HockeyApp, Insights and Test Cloud Live!
After the Microsoft acquisition, the mobile DevOps toolset at Microsoft is pretty complete. As became clear in the Keynote, Xamarin Insights will merge into HockeyApp to become a compelling tool for deploying and monitoring apps. Donovan Brown from Microsoft came on to rub some DevOps on all of this and walked us through those tools.

The keynote ended with a sweet “one more thing” moment: the announcement of Test Cloud Live. Wow! Ever had your app crash on some obscure device and had a hard time tracking down that bug? Well, now you can attach your debugger to that device in the Xamarin Test Cloud and start debugging your app! Mind blown!


Bear in mind that you’re debugging over a network connection to a device that sits in the Xamarin Test Cloud device center in Denmark, and the technology is early preview, but this is so promising!

I was amazed by all the announcements, especially how fast Xamarin was able to open source all of their stuff and release the new goodies.

Breakout sessions

For the breakout sessions, I mainly looked for sessions that were not so much technical, but more inspirational to get some nice new ideas.

Contextual CommunicationBrent Schooley
Brent is from Twilio, who are experts in communication technology, but he did a great job not making this talk about Twilio. Instead, I found this an inspiring talk about improving and modernising business communication.

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The main 4 tenets he highlighted are that communications should be:

  • Contextual: what do you already know about the user/customer? Context matters to make communication more personal and …
  • Streamlined: if you can leverage context, you can get down to the point quickly and make conversations as short as possible
  • Secure: again, if you leverage context and what you already know about a user, you don’t have to communicate that information again every time. This saves you from exposing security or privacy sensitive information.
  • Medium of Choice: the customer must be able to choose his/her medium of choice. So an app cannot be the only option. Some people prefer to call or use chat.

Brent demonstrated this with an inspiring demo-app where he started a call from inside a fictitious airline app, and had information (context) exchanged automatically into the app during the conversation to get through a transaction in a streamlined manner. He then used TouchID to verify the customer’s identity to finalize the transaction (secure).

He also covered the new “Bots” trend. With Microsoft’s new Bot Framework and Cognitive Services, we can build interesting things to make these conversations as contextual, streamlined and secure as possible and reuse that across different media. It remains to be seen if 2016 will indeed be the year of the Bot.

I really enjoyed Brent’s talk; he definitely made me think about interesting use cases to improve communications by looking beyond “an app for one single process”. This is what I will focus on at Xpirit for our Mobile strategy.

Clicking on the Real World with iBeacon – Jim Bob Bennett
Similar to the previous session, this session also worked as an inspirator for me to look beyond that one app on the device that your user interacts with. iBeacons are a great way to make the physical world your interface. For example: as I walk into a Starbucks, using iBeacon, they can recognise that I’m entering the shop and know which coffee they have to make so I can walk right up to the counter and pick up my double espresso and pay with my credit card linked to my Starbucks account. Cool. Jim Bob showed how to do this with the iOS CoreLocation API’s.

Unfortunately I had to leave the iBeacon session early, to be in time for my DevOps discussion panel at the Mobile Leaders Summit.

The Future of Connected Devices with Philips hue – Eric Shapiro, Sait Izmit, Mike James
To be honest, I was a bit disappointed with this session, as it was mainly a product placement session for Philips hue, driven by videos instead of much substance. The interesting part for me was Mike’s part in this case, where he showed how to develop against the hue bulb using the Q42.HueApi SDK.

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Adventures in PerformanceMark Probst
This session was a deep dive on the way Xamarin does their performance benchmarking. It was a little bit different than I had expected, but interesting and entertaining nonetheless. I really appreciated Xamarin’s transparency: Mark spoke about some of the challenges they had in the Garbage Collector and the experimental ways they are trying to improve performance and bringing down GC pauses. Really some clever stuff!

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No big lessons here, except appreciation of Xamarin’s transparency and respect for the smart guys working on the Mono runtime.

Xamarin Party!

In the evening, we celebrated Xamarin Evolve 16 at the Wizarding World of Harry Potter theme park. We took all the rides, including the crazy intense roller coaster and the big splash over in Jurassic Park. The food and the vibe were awesome!

I didn’t get to take many pictures, but there’s a lot of that going around on the #XamarinEvolve Twitter feed.

I’ll leave you with some inevitable food pics and some from the party 🙂

Dumplings #food #xamarinevolve

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Golden Snitch popsicles #food #xamarinevolve

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Jurassic Park! #XamarinEvolve

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T-Rex #xamarinevolve

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Xamarin Evolve 16 – Training Day 2

Time flies! The second day of training at Xamarin Evolve is over already and I just came back from the awesome opening party in the Darwin Lounge.

The main conference starts tomorrow. I’m honored to be on stage with some industry giants at the Evolve Mobile Leaders Summit track in a panel discussion about The Unique Challenges of Mobile DevOps. But that’s tomorrow!

About today: before the training, the day started at 6:15am (!) with a 5k test run with for the first Mini-Hack tomorrow morning. I spot an orange Xpirit T-shirt 🙂

The training part was another intense day from 9am-6pm, but it was a good day. I’d say the content of today was a bit better and deeper than what we learned yesterday, at least for me personally. We covered three major topics:

Securing local data
This part was all about dealing with data locally on the device, especially sensitive data in terms of privacy and security. We had a look at what the Xamarin.Auth component has to offer for local storage of sensitive data. This component (you can find it on GitHub and on Nuget) uses the platform specific facilities for storing data in a secure container, i.e. the KeyChain on iOS and a secure KeyStore inside the app’s sandbox on Android.

Be sure to get the latest 1.3.0 version of the Xamarin.Auth component though, as this is a bait-and-switch PCL library that also offers support for the Windows platform, whereas the older 1.2.x version doesn’t.


There’s one caveat with the Xamarin.Auth component though… The KeyStore file on Android is locked with a hard coded password. The Android app in one of my previous projects was actually flagged in a security audit because they extracted the Xamarin.Auth DLL, decompiled it and found the hard coded key. Pretty iffy, because this means that the KeyStore data in every app that uses this library can be easily opened and read by extracting the file from the sandbox and using the key that’s publicly available on GitHub!

I made a pull request about 2 years ago that fixes this problem, at least in a way that you can provide your own key. But somehow Xamarin didn’t get around to merge it yet, so the vulnerability was still there, also in the 1.3.x version. The funny thing was that as we were doing the training, one of the Xamarin developers was actively working on this component. We pulled him into the training, explained the problem and he immediately went to work to see if he could merge my fix. How awesome!

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How awesome is this: Xamarin Developer DNA… everyone could add their own string, picking the pegs that fit with their preference. The result is this awesome, unique “Xamarin DNA” sequence. A work of art!

The other part of this chapter was about the awesome PCL.Crypto component. This component is also a bait-and-switch PCL library, which means that the PCL portion contains nothing more than the API definitions for your shared code to compile against (the bait), but uses the actual device specific implementation at runtime (the switch). This means that PCL.Crypto can use the platform specific crypto API’s developed by Google, Apple and Microsoft themselves instead of relying on its own security implementation. Much the same as the Xamarin.Auth component solves its local storage issues. For developers familiar with the WinRT crypt API’s for example, there is a special WinRTCrypto API that you can program against, but PCL.Crypto will map this to the underlying native API’s. Pretty clever. For example: a method for encrypting some data could look like this:

public static byte[] Encrypt (byte[] plainText, byte[] keyMaterial)
  var provider = WinRTCrypto.SymmetricKeyAlgorithmProvider

  var key = provider.CreateSymmetricKey(keyMaterial);
  var IV = WinRTCrypto.CryptographicBuffer.GenerateRandom(16);
  var cipher = WinRTCrypto.CryptographicEngine.Encrypt(key, plainText, IV);

  var cipherText = new byte[IV.Length + cipher.Length];
  IV.CopyTo(cipherText, 0);
  cipher.CopyTo(cipherText, IV.Length);

  return cipherText;

PCL.Crypto can be used quite easily in combination with Xamarin.Auth to encrypt or hash data before storing it. At least as long as your app is using the not-so-secure version of Xamarin.Auth – with the hard coded key – using something like PCL.Crypto to secure the values that go into the secure storage is a real necessity! But it’s good practice to do it anyway.

Next we went into OAuth for authorizing access to an API from a mobile app. OAuth in itself is a pretty broad topic and enough to fill tens of blogposts. One of the important points here is that for mobile apps, basically there are only two OAuth flows that are really usable:

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The Implicit flow or the Authorization Code flow. The other flows aren’t really suitable for mobile apps (or browser apps involving JavaScript code), since this means that there will be client secrets hidden inside the app, and they involve dealing with a user’s password in the app itself instead of handing that off to an Identity Provider. The Client Credentials flow is typically used for service-to-service communication, usually on behalf of the user.

Xamarin.Auth provides some nice API’s to easily initiate a login sequence, using a web view that follows all the redirects that are part of the OAuth flow, to obtain an access token (or authorization code).

Memory Management Issues
The most interesting part of today was about diagnosing and dealing with Memory Management Issues. I actually learned a lot about how both the Xamarin.iOS and Xamarin.Android frameworks work in terms of memory allocation. It’s important to understand that in both cases, you are always dealing with native objects, managed peers and a binding layer in between, provided by Xamarin. At least, for those objects that are actual native platform classes.

Under the hood, there are some intricacies to be aware of. For example: in order for iOS’s reference counting mechanism to work, you have to be very careful to release references to native objects, for example by making sure to always unsubscribe from event handlers. For Android, it’s important to realise that you’re working with two Garbage Collectors: the Mono one and the one in the Android Java VM. There are a lot of details, but there is some nice guidance up on the Xamarin Developer site about this [iOS] [Android].

You can prevent a lot of memory issues by following a couple of important guidelines. Also the Xamarin Profiler is a great tool for diagnosing possible memory leaks.

Lots of excitement for the opening of the Darwin Lounge at #XamarinEvolve

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Darwin Lounge
As for the (other) fun part of Evolve: the Darwin Lounge was opened this evening, accompanied by a huge buffet and a nice range of tasting stands for artisanal chocolate, local beers and hipster coffee 🙂 This tweet sums up how I felt this evening:

It’s no secret that I’m an avid foodie, so suffice to say that I was in seventh heaven when it comes to the food that was served here. This means that you have to sit through my Instagram food porn pictures now:

Excellent chocolate. The Phillipines one is a clear winner #food #XamarinEvolve

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Great hipster pour-over coffee at #XamarinEvolve

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Hmm, macarons #XamarinEvolve #food

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Beer tasting at #XamarinEvolve. Local beer from Orlando Brewery. Good stuff.

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So… Xamarin sure knows how to throw a party 🙂 Of course, the Darwin Lounge at Evolve is mainly about cool geek stuff and tech inspiration. There’s lots of that going on as well. Lots of IoT stuff, drones flying around, etcetera. Check out the Twitter timeline for #XamarinEvolve for a great impression of the fun things out there.

Great buzz and lots of hacking going on in the Darwin Lounge
These robot spiders are pretty creepy!
LEGO Mindstorms, totally cool! Their official iPad app for programming the Mindstorms robot was built with Xamarin

Be sure to tune into the Evolve keynote tomorrow at 9am EST. Rumours are that it’ll be spectacular! 😉

Thoughts on the Xamarin Evolve 2014 keynote

Wow, Xamarin certainly pulled off a great one in the Evolve 2014 keynote today. I had to miss the conference this year but I sat behind my MacBook watching the keynote in high anticipation regardless.


The keynote was a rollercoaster ride, and the team can be very proud of what they have achieved. Xamarin is clearly on a roll! Let’s go over today’s highlights (at least, for me)…

The vibe
Evolve 2013 was a fantastic conference, mostly because of the awesome vibe. The Xamarin team was visibly proud, and the whole atmosphere during the conference made it great to be a part of. From the tweets in the #XamarinEvolve stream, it seems that they pulled it off again this year, despite the much larger scale. Kudos to Nat, Miguel and their team for that!

The great vibe was also noticeable in the keynote. It’s really great to see a CEO and CTO on stage – who are themselves just geeks like us – radiate with pride and excitement. And a little bit nervous as well 🙂

The Digital Business
One important thing that was recognized in the keynote was that the Digital Business is becoming top priority for C-level executives in the enterprise. This enables interesting scenarios for mobility and cloud to change the way employees do their day to day work.

Avanade mentioned in the keynote that CxO’s are focusing on reach, recognising the fragmentation in the mobile arena regarding devices, mobile OS-es and the variety of device flavours. BYOD is happening, which means that a good cross platform scenario is very important.

At the same time, user experience is a huge part of the story. As Nat rightly remarked:

Your app, even if it’s an enterprise app, is next to the best apps in the world on someones phone.

As a result of the consumerization of IT, users have come to expect top notch UX from their enterprise apps as well. Just as smooth as their consumer apps. Needless to say that the reason why I love Xamarin is that they bridge cross platform development and native experience in the best way I’ve seen.

IBM partnership and Mobile Middleware
Mobile middleware is becoming a real necessity in the enterprise. Opening up enterprise backend systems to mobile devices isn’t just like regular EAI – Enterprise Application Integration. We have to deal with very different connectivity scenarios, new security threats, and performance constraints that come with mobile devices. This opens up opportunities for new and interesting architectural styles and cloud based backends. A company that – IMO – gets this very well is KidoZen.

IBM is now also stepping into this new world of mobile with their Worklight product. Very interested to see where the Xamarin/IBM integration is going.

Xamarin Forms Partners
Xamarin.Forms is a very promising framework, in which Xamarin balances cross platform development and native user experience in a very elegant way.

The contributions from the Xamarin.Forms partners fully brings the framework to life, with awesome powerful controls. Charts, document handling, advanced user inputs, etcetera. This is a very nice step towards adulthood for Xamarin.Forms.

Xamarin Profiler
With these constrained mobile devices, performance efficiency is very important. For this reason, you’ll find yourself spending a lot of time running your apps through profilers to get out all the jitters and memory leaks. Xamarin now has a great profiler that actually looks at the app from a Mono/.NET point of view. Can’t wait to play with it!


What I really like about the new tools is that Xamarin is taking their own advice to heart: create native experience on the target platform. This means that the Mac versions of the tools have the distinct OSX style, and the Windows versions have that recognizable “Metro” look (I still call it Metro). It’s the details that matter, and I like it.

Xamarin Android Player
Every Android developer knows how excruciating the Android emulator is to use. Although it’s an accurate emulator, it’s dreadfully slow. Many have already defaulted to using Genymotion, although that may cause integration problems, for example with VirtualBox if you have a Windows VM running in Parallels on your MacBook like me.


The Xamarin Android Player is much faster, and integrates neatly with other IDE’s that speak ADB.

Now, the player won’t excuse you from testing with real devices, but this greatly improves the developer experience! Wow, well done Xamarin!

Xamarin Sketches
You could expect from Xamarin that they’d take Roslyn and do something great with it. Xamarin Sketches is a nice REPL like tool that helps you draft up C# snippets, have them executed immediately and park them as snippets. Web development style immediate feedback with C# development!

I love how Xamarin brings the IDE closer and closer to Brett Victor’s vision in his Inventing On Principle talk, similar to what Apple did with their Swift Playground.


In addition, the real time integration with the emulators, where you immediately see code changes being executed, is a huge productivity boost! Amazing piece of engineering from the Xamarin team!

C# Test Automation
Now finally we can write our automated UI tests in C#!

Xamarin Insights
A good solution for monitoring the stability and quality of your apps, out there on all those devices, is crucial. It helps to detect problems and keep the quality and user experience on a high level. Moreover, monitoring your apps behaviour can give you a lot of new insights.

There are several solutions in the market that can help you track errors, and even do a bit of performance monitoring. Services like Crashlytics, Crittercism, Raygun and even my favourite APM tool New Relic all have mobile offerings.

The problem with these is that most of them hook into native API’s to do their work. This means that you’ll need a C# binding for their SDK’s to use them in your Xamarin app. For example, Raygun has a component in the Xamarin Component Store you can use. Still, catching errors won’t give you all the details you might be looking for as a C# developer. You’ll want to have the full .NET/Mono stack trace and more details from the Xamarin environment that you won’t get if you don’t have a “Xamarin native” SDK.

Furthermore, monitoring app performance will be difficult, again since most APM SDK’s hook into extension points in the underlying native framework. With the New Relic SDK for iOS for example, you’ll find yourself trying to hook measurements onto Objective-C methods, selectors and other extension points, whereas you really want to know how your C# method is doing. These SDK’s also make it difficult to instrument shared code, since their API’s are usually platform specific. Again, a “Xamarin native” SDK is lacking here. I really hope New Relic has a Xamarin compatible SDK on their roadmap. But now, luckily Xamarin has taken up the challenge themselves…

Enter Xamarin Insights! I’ve already had the privilege of playing with the platform a little bit, and things look very promising. There is still some work to be done on the performance monitoring part, but the error tracking and alerting feature is shaping up very nicely.


Xamarin is growing up fast. With the addition of Test Cloud, Insights and the new Profiler, they’re building a great one-stop solution for mobile development. Sketches, C# test automation and the fantastic new Android Player make the developer experience even more delightful.

Congratulations to the whole Xamarin team!

Xamarin Evolve 2013 – Day 4

And so, Evolve 2013 has come to an end. Time flies when you’re having fun. This was day 4 for us in Austin. Four days of Xamarin mobile goodness.

This was another interesting day. It started off with a session by Josh Clark from Global Moxie, and author of Tapworthy on user interface design and touch. While his message – have users directly interact with content instead of indirections, such as buttons – wasn’t revolutionary, he had a couple of nice and inspiring examples to show us. Apps that have implemented some innovative UI’s. A nice session to start the day with.

Oh, and he had a picture of an OCD Chef’s cutting board… man I gotta have this in my kitchen 🙂

LOL, I want this in my kitchen! #xamarin

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After that, I went to Marek Safar‘s session on Using Async in Mobile Apps. He shared some good tips and pointed out some pitfalls around SynchronizationContext when using Async.

Most of the day was spent in the hallways of the Hilton though, talking to people, meeting all the faces I have in my Twitter stream in person. This was awesome. Great to share a passion for mobile development with Xamarin and talk face to face about our experiences. Thanks Greg, John, Wally, Ben, Nic, Stuart, Miguel, Nat and all those I forgot to mention for catching up.

Of course, Marcel (@marcelv) and I did our own session titled “Sharing 80% of Code on iOS, Android and Windows Phone”. We decided to give our own take on code sharing, and how to achieve this in a low barrier, simple way. We spent a lot of time during the conference, speaking to developers with all different levels of coding skills and we found that a lot of them were impressed by some of the frameworks and approaches that were being presented for achieving code reuse, but for whom all of this went a bit over their head. These frameworks tend to hide a lot of clever tricks, and you also run the risk of over-abstracting. So we took our lessons learned from a real life example app we built for a customer, and explained some small but clever architecture and coding tricks.

We got great response afterwards, and got some requests for sharing some of our code. Marcel and I will be working on a blogpost, showing all of the constructs we presented today. Have an eye out for Marcel’s blog. We’ll put it up there and I’ll cross post it here as well.

I visited Nic Wise‘s session about MonoTouch.Dialog as well. It’s tough to be the last session of the day, but he did a good job. I’m not entirely convinced that MonoTouch.Dialog is a solution in every scenario, but it does provide a neat way to quickly code up an iOS UI.

So after that, it was time for the closing keynote already… Nat and Miguel announced Evolve 2014, and in order to show their commitment, five lucky birds in the audience won a ticket. Awesome, can’t wait for the next installment of this awesome conference.

#Xamarin Evolve 2013 is a wrap!

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In closing, I’d just like to give my compliments to the whole Xamarin staff and the production company for putting together an inspiring conference. I loved the attention to detail that was visible everywhere. I enjoyed the vibe, the great food, and the fantastic content.

See ya’ll next year!

Xamarin Evolve 2013 – Day 3

Day 3! Or actually Day 1 of the Evolve conference, to be exact. And whew what a day!

Of course the conference kicked off with the keynote by Nat and Miguel. What a well produced and slick show! A big stage, with gorgeous graphics on the big projector screens, awesome. You should definitely check out the video of the keynote here. We were proud to see Info Support there as Silver Sponsor:

Let's go! #xamarin

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Xamarin blew everyone away with a couple of great product announcements today. Only six weeks after releasing Xamarin 2.0, four major new features were announced:

C# 5.0 async/await
This C# compiler feature enables much cleaner syntax for async programming, resulting in better readable and shorter code. Moreover, less chance of bugs due to event handlers dangling around. Async/await was announced by Xamarin a short time ago as a beta, but available as of today in a final version.

For those who like functional programming, F# is now a first class citizen in the Xamarin stack as well. I’m still new to F# but I’ll definitely check it out. A nice addition.

But the biggest features, that got the whole audience exploding were…

iOS User Interface Designer
WOW! This was some rabbit Miguel pulled out of his hat. An iOS UI designer embedded in Xamarin Studio, to replace having to resort to XCode’s Interface Builder. And it does not only replace it very well, but goes way beyond what IB does. Besides looking gorgeous, the designer tightly integrates with the code generator in Xamarin Studio. Adding controls to a view automatically adds member variables to the class. Actually they’re still outlets, but you won’t have to worry about them. So dragging lines from UI elements to Objective-C code files is over. I used to get so many smirks from Visual Studio developers when I demo Xamarin / XCode integration in my talks. This is all over now. No more explaining what an outlet is, because… as Miguel mentioned in his talk:

I am glad though, that Xamarin stayed closed to the Apple structure when it comes to the generated code. As far as I can see, the designer generates code that is compatible with code coming from the XCode integration. Controls are still marked with an [Outlet] attributes, etc. I have yet to try the designer myself, but I assume that XIB files and storyboards are instantly usable with the Xamarin designer.

Furthermore, any UI component that you might have in your solution, be it from the Xamarin Component Store, from a referenced DLL or self coded in your project, automatically becomes available in the designer. And what’s more, it shows a live preview of the control at design time!

I really didn’t expect this designer to be available so soon. I had seen screenshots and ideas from Miguel but I thought that it was still some time away from becoming a real product.

Again, kudos to the Xamarin team!

Like Miguel mentioned… If you ever think “Xamarin should do UMMM…”

Xamarin Test Cloud
Again, WOW! After the iOS designer, people weren’t expecting any more stuff. But then Nat came on and introduced the Xamarin Test Cloud. A fantastic new product that does automatic UI testing for virtually every smart phone or tablet device available on the market. Xamarin actually acquired LessPainful solutions for their infrastructure. Basically, Test Cloud is a test service that uses real, physical devices to run UI tests on, based on exploratory testing (i.e. hitting every feature in the app) or a prerecorded test script, expressed in Given, When, Then construct.

Here’s Xamarin’s own introduction page on Test Cloud: link

TechCrunch has written a nice introduction article on this as well.

So that was a shocker for the audience. Awesome. This is a major step for Xamarin though. With this completeness of vision, I think Xamarin will win over a lot of customers that were reluctant to come along with the Xamarin tools. Customers, at least the ones we’re servicing, were a bit reluctant about the maturity and completeness of the holistic vision and approach of mobile development. I think today, Xamarin nailed that question!

The sessions following after that were mostly good. I enjoyed Stuart Lodge’s session on MvvmCross, Sebastien Pouliot’s session on Advanced Build Mechanics for iOS and of course Scott Hanselman’s session, which was basically a nice celebration of the C# language.

And of course I enjoyed doing our own talk about creating a uniform login experience across devices. We’ll put the accompanying slides and source code online as soon as we have a chance.

Then the day ended with a Food Truck party in Brush Square Park across the street. Austin is famous for its food trucks, all specialized in a certain type of food. And they’re good! I had a Tex Mex style wiener, which was really nice and spicy, a nice corn flour tortilla wrap with chicken, cilantro and chilli. As a desert, there was ice cream. Not just regular stuff, but… salted chocolate and red velvet cookies. Heaven, for a foodie. Again, a great vibe among the conference visitors.

Xamarin just ordered 7 food trucks, all great stuff 🙂

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Red velvet cookie & salted chocolate ice cream… Goodness! #xamarin Foodtruck party.

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After the foodtrucks were closed, we got together at Maggie Mae’s for more partying. Austin has a nice vibe, there’s live music all around.

So tomorrow is the last day of the conference already. How time flies. There’s one more session for Marcel and me to do. This one will be about code sharing. We’ll dive into some of the more detailed, sometimes basic type of tricks and architectural patterns you can apply to achieve more code sharing but still leave the app easily maintainable.

See ya in our session tomorrow!