Recently, Microsoft ended up buying Xamarin. It was very much anticipated, it always felt more of a "when" than "if" and finally it happened. Microsoft made the Xamarin suites (most of it) available with the MSDN licenses. It removed a barrier for a lot of companies and independent developers. Now, if you're a .NET developer and want to build a cross platform application, you may not have to look beyond Xamarin.
In today's Enterprise world, the use of TFS is prevalent. It usually tends be an on-prem one. Thankfully, TFS allows us to create Git repositories. For now, it only supports HTTP. SSH is coming to TFS with Update 3.The timeline for features is here. I have also seen the on-prem TFS version is slightly behind the cloud one. The features mentioned here are not available in an on-prem version. There is some starter documentation by Xamarin but it may not be enough to see you though turbulence.
For the Xamarin apps, the Mac TFS build agent has gone through a lot of churn. It used to be VSO Agent.It is being deprecated in favor of the VSTS agent.The new agent didn't support on-prem TFS until version 2.101.0. I learned it the hard way. It is in a preview state as of June 20th, 2016. It lacks community support. If you hit a road block, you may have to dig into code yourself (yay, OSS!) or open up a ticket on GitHub and wait for the team's reply.
Based on the feature gaps between visual studio online and TFS on-prem, lack of community support, confusing MSDN articles and issues with the preview version of Mac Build Agent, I'd recommend not to use TFS for the continuous integration purposes, at least for now. They are moving in the right direction but not fully there yet.
Instead, the better option is Jenkins. It is free. It has a great community behind it. It has rich plugin ecosystem. It has a nice upgrade and downgrade functionality. If for some reason, upgrading a plugin or Jenkins itself is not working the way the previously installed version did, you can simply go back to that version without too much of a hassle. In other words, it just works!
The next post in the series is available at http://aradhye.com/continuous-integration-for-xamarin-app-with-jenkins-and-deployments-with-hockey-app/