query: Serving ads only for users who didn't buy application
positive_passages.docid: 4297
positive_passages.text: Change paid app to free but know if user previously purchased it
negative_passages.docid: 109030
negative_passages.text: Open-source ads: are they really displayed on Stackoverflow?
negative_passages.docid: 80492
negative_passages.text: Allow only RemoteApp, not Remote Desktop
negative_passages.docid: 91041
negative_passages.text: Ad Blocker detection AKA Adblock Plus
negative_passages.docid: 79178
negative_passages.text: Allowing users to edit only their page and nobody else's
negative_passages.docid: 128331
negative_passages.text: Creating an Android trial application that expires after a fixed time period
negative_passages.docid: 51918
negative_passages.text: Will Stack Exchange 2.0 websites stay free of ads for the next 2 years?
negative_passages.docid: 137126
negative_passages.text: How Do I Allow A Standard User to Install Programs?
negative_passages.docid: 137470
negative_passages.text: How to restrict anonymous users to a single product and quantity 1 using Commerce and Rules?
negative_passages.docid: 47553
negative_passages.text: Application Only for Tablets
negative_passages.docid: 8756
negative_passages.text: Use VPN connection only for selected applications
negative_passages.docid: 12348
negative_passages.text: How Do I Opt Out of Privileges?
negative_passages.docid: 41935
negative_passages.text: Let's stop displaying a user's accept rate
negative_passages.docid: 101235
negative_passages.text: Banner ads should not be shown on the right-hand ad slot
negative_passages.docid: 38527
negative_passages.text: How to disable third-party apps without uninstall?
negative_passages.docid: 119645
negative_passages.text: How to make a process invisible to other users?
negative_passages.docid: 43045
negative_passages.text: Prevent applications from opening browser