If I understand correctly, you want to be able to have the same login for your users when they use the AppManager mobile app and when they use the apps that you distribute. If this is so, the solution would rather be to use a login provider that we also support (since exporting usernames along with passwords from our DB via public API is not a very safe option).
Currently, we do not offer integration with login providers, but if it gets requested a lot, we can add it to our roadmap. You can add such request in our feedback portal, so others can vote for it, too:
Telerik Platform Ideas & Feedback Portal
Check out the Telerik Platform - the only platform that combines a rich set of UI tools with powerful cloud services to develop web, hybrid and native mobile apps.