O'Reilly logo
  • Dave Burke thinks this is interesting:

You could use a similar technique for distributing shareware versions of an Android app (i.e., limit the number of trials of the application). In this case, you would use an integer count value in the preferences to indicate the number of trials. Each trial would update the preferences. After the desired value is reached, you would block the usage of the application until the user pays the usage fee.


Cover of Android Cookbook


Good idea!