Here's the list of capabilities an application can have, straight from the WP8 SDK. This doesn't include any secret capabilities for OEMs that would be used for homebrew, assuming they exist.

Of interest are the ones towards the bottom, including wallet, payment instruments, secure element, proximity, and removable storage.

For kicks, here's the requirements you can list for your app, preventing it from being installed on devices lacking these features:

Any questions? ;)