Why did you stay on such an ancient OS? You likely are using a version of the App Store which doesn't support pinning older OS releases on older app releases e

Why did you stay on such an ancient OS? You likely are using a version of the App Store which doesn't support pinning older OS releases on older app releases either -as soon as they released a build for iOS 7, the iOS 6 version would no longer be accessible. You are also missing about seven years of security updates, including several browser-accessible remote exploits. Not using Safari would be a good idea.