So, you know fancy new fingerprint reading home button Apple showed off for the iPhone 5s at today's event? The company demonstrated functionality for unlocking and buying stuff through iTunes. Cool, but what about third-party apps? We can imagine all sorts of neat uses not limited to buying stuff. For the time being, however, the authentication functionality is off-limits. Apple exec Phil Schiller told All Things D that the hardware won't be opened to developers initially. As to whether that functionality will be arriving in the future, Apple's not ready to say just yet.