I have an App for WP 7.1 to access photos stored on the phone, so I have enabled capability "ID_CAP_MEDIALIB. When testing the application from Visual Studio in WP8 emulator is fine, but if I implement the XAP in emulator (or send it to certify) gives me error accessing the images.
I've finally discovered that the problem is because in WP8 the capability ID_CAP_MEDIALIB_PHOTO it's needed.
The question is, how can I add this capability to use in WP8, but at the same time I keep it running on WP7?. Because Apps for WP7.x must run on WP8 (at least I have not seen how exclusive for WP7.1)