How to implement trialware model on Android?
<p>Any tips on how to implement a trialware model for Android apps? I plan to release my app as a free app that expires after 30 days unless the user buys the license via an in-app purchase.</p>

<p>I can use the Android Market API to tell if they bought the license, so <strong>my main question is how to prevent the user from un-installing and re-installing my app every 30 days</strong>? Can I save something to their phone in a permanent and reliable way that will remain on the phone even if they uninstall? I know nothing will stop a determined hacker, I just want to stop the average user.</p>

<p>I am also open to different approaches to going trialware on Android.</p>

<p>Thanks in advance,</p>

<p>Barry</p>
