Time limits for trial version of application

Question

I am looking to make a trial version of an app I made. Basically I want to put a time limit on how long the app will function before a window comes up that states that the user must buy the paid version of the app.

Thanks for any tips ahead of time!

Answer 1

When your application is installed for the first time on the device, connect to your server and assign it a unique id for the device.

Every time the application is started, check for the expiration date corresponding to the device and show appropriate message when the trail period gets over.

Or otherwise, disable a few features and release them only when the user buys it.

Don't use SharedPreferences because the user can easily clear the application data and the time would be reset.

Answer 2

Use a server with a database that stores phone id's and dates. Then retrieve the status for the current phone. When the user installs a new rom, the id will change, so that should not be very often.