An application I was testing asked for user location on first device launch. I have uninstalled the application, deleted the build folder, and cleaned all targets, but core
Not many people know this, but after you uninstall an application, that application's documents and preferences are still stored on the device, here:
/var/mobile/Library/Safe Harbor/myappidentifier/Container/
in my opinion, this was not a wise move by apple, as that could have security risks, as the one you have explained above.
If an app is re-installed, iOS automatically copies those preferences back into the appropriate folder. That is the cause of the behavior you are seeing.