Originally Posted by
techie
In the spirit of honesty, iOS 7 is supported and can be installed on an iPhone 4. If you choose not to do so, that is on you. Besides, it is becoming more and more of an accepted practice to provide app support for only one iOS release back. This is why a lot of apps have gone "iOS7 and later" last week. My 4.9.x version of the app works just fine, so it's not like things go completely broken.
Specifically told that "it wouldn't be advisable" to put iOS7 on the iPhone4 by the Apple Store ... and I'm guessing that if I went online now, it wouldn't allow me to download iOS7?
Nonetheless - when iOS7 was the top version of the OS, BA didn't support iOS6 for the App.