I created an app with Visual Studio 2015 in this way : new Project -> Visual C# -> Windows -> Windows 8 -> Windows Phone.
My question is , is this app compatible with windows phone 7? I read something that the WinRT can make this happen, but I am not sure.
I tested the app on an Samsung device with Windows Phone 8.1 and it worked perfectly, can I assume that it works on Windows Phone 8 the same?
What about Windows 10 mobile? Is a Windows Phone 8.1 app installable on a device running on Windows 10 mobile?
I read the Wikipedia article about Windows Phone 8, but I did'nt get the information I was looking for.
Your app will work on Windows Phone 8/8.1 and Windows 10 Mobile.
It will not work on Windows Phone 7 devices.
My advice is to check better how it works on Windows 10 mobile - you might have surprises where the UI is slighlty different or some controls won't work as expected.