It looks like your problem is that you're using the Android Support packages for 25.x. UI for Xamarin doesn't support API 25. Go here to see the required dependencies
(this is a good page to bookmark).
Once you update the package versions, you should be good to go. As an example, I've attached a sample app.
For future reference, I highly recommend using the Telerik Project Wizard
, this will create a full Xamarin Forms solution for you with all the required dependencies, renderers and project references. It's a great reference project to have whenever you need to check what should be added. It only takes a few seconds to create a solution with projects for every platform.
I see that your DevCraft Ultimate License expired on March 12, 2017
. We use a perpetual license approach, this means that the only fully licensed packages available to will be the ones released during your active period (3/12/2017 to 3/12/2017). However, this also means that any future releases will be trial packages.
This is just something to keep an eye on, make sure you don't unintentionally upgrade your Telerik nuget packages to trial release of a product.
Lance | Tech Support Engineer, Sr.
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