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I am new to developing IPhone apps and this is my first attempt.I have made a simple app which has two buttons in it. One button opens a URL and the other opens a Pop-up window.I am yet to enroll as an apple developer and am testing my application on the physical device by connecting it to Xcode.When I install the application, it runs properly for a few days in spite of disconnecting it from XCode. However, after a few days, the application does not open and flashes a black blank screen and goes back to the home screen.When I reconnect it to Xcode and run the same code again on the same Iphone, it again works properly for a few days and then crashes again.I am unable to understand why is the app behaving in such a manner after a few days and not immediately.Is there some expiry period for application when one has not signed in as a developer?(The provisioning profile shows expiring soon)If not, can you please guide me as to how to go about troubleshooting this issue?Kindly give me your esteemed suggestions/comments as I am badly stuck and need to find a solution as soon as possible.Thanks a lot!