System app data is also not backwards compatible.
For example, you can use TB to import your contacts from CM7.2 to CM9.1 but you can't do the same the other way round. I learnt it the hard way...
XDA Developers was founded by developers, for developers. It is now a valuable resource for people who want to make the most of their mobile devices, from customizing the look and feel to adding new functionality.
Are you a developer?
Copyright © xda-developers. Hosted by Leaseweb