I have developed an application that I want to share with my clients. I want to share its trial, taking care of following points
- Application should expire (i.e. User cannot move from main activity) after 30 Days
- Internet connection is not required for my application so I don't want to manage trial expiration by managing a server where device's IMEI can be stored or sort of thing.
- I want to restrict user from using application even if he uninstall and later on re-Install my app.
- I want to protect application trial against a manual date changing hack normally applied by users
I was planning to maintain a file for my application with time token of first run saved in it which can be compared with GPS time on each run but the issue I am facing here is of file storage. If I save a file in Internal memory it gets deleted with application un-install and cannot be used when user reinstalls the app and if I store it on SD card/ External memory it is vulnerable to user deletion. I have investigated this issue from everywhere I can but got no success. Any idea or suggestion by you guys would be a relief. :-)
There will have internet access when the app is installed, or they wouldn't be able to install it.
Simply require that the user activate the app with a server the first time they use it. The app gets a "this app was first activated on yyyy-mm-dd" response from the server, and stores that info on a file in internal storage. From that point on, the user won't need to be on-line to use the app.