Differences between Windows Phone 7.x and 8.x APIs

I've received several emails asking about the differences between the supported APIs on Windows Phone 7.x (currently, 7.5) and 8.x (currently, 8.0). Usually, older 7.x applications migrate seamlessly to the new platform, but of course, there are differences, too.

On MSDN, you can find a good list on all the major differences, and this article is titled "App platform compatibility for Windows Phone".

If you are interested in what are the breaking changes between WP 7.5 and WP 8 applications, be sure to check out this list.