Trial Applications Best Practices for Windows Phone
This topic describes the best practices you should consider when you create a trial application.
Do not rely on usage time limited trials to protect your application’s value.
Typically, it is best to protect the value of your full mode application by limiting trial access to key code paths. A user may uninstall and retry an application without restriction so a trial design that offers full mode behavior for a limited time provides only inconvenience as a barrier to reuse.
Cache license state if you check trial state frequently.
Check the IsTrial() state when your application loads or resumes.
You can avoid some potential trial design flaws especially if you cache the IsTrial() state.
Provide a way for users to buy your trial application before the end-of-trial.
Make sure that you help users understand why they want to buy your application, perhaps, by implementing your trial limit at a point in the application where they will naturally want more.
For example, let users experience the first level of game play and require them to purchase the application to play higher levels, retain points, or to connect to a gaming service.