I purchased AcroBible out of Play Store. Paid for the higher end version. I have used it for months, but today in church (which has no wifi), Nexus would not let me open the Bible, giving me the message "Application not licensed. Unable to validate application license". fortunately I have the same app on my Iphone, which has NEVER given me any trouble. If I have purchased and downloaded the program, why is it necessary for me to find a wifi hot spot for me to use it?