Steve Litchfield has a Plea for Simpler Registration for mobile phone applications. Currently, most of those bind to the IMEI of the phone, which makes switching your phone difficult because you’d have to contact each developer for a new code, leaving those with the difficulty to judge whether there really is a new phone or somebody is just trying to get a registered version for a friend for free.
The availability of network connections on the phone should make it possible to de-register apps online and re-register them on a different phone, without locking them to the IMEI. You could just give out “credits” that could be registered or de-registered with a password. That would be perfect with a standardised library that all developers could use, and integrated with some of the popular shareware resellers like Handango, don’t you think?