I'm new to iOS dev and Swift.
I started my game using Swift 2.3. Sent it for Preview to Apple, they rejected it yesterday because a few functionalities were not working on iOS 10. So I had to update my iPhone 6S to iOS 10 in order to test it accordingly.
When doing that, my XCode 7 obviously requested me to update otherwise I couldn't install my game back again on iOS 10. Which I did.
When installing XCode 8, suggested me to migrate to Swift 3 (recommended). That was the worst choice I could ever pick since now my code has more than 240 errors including syntax ones from 3rd party libraries such as GoogleAds, iCarousel, etc. I wouldn't have any problem on fixing those 240 errors if they were all mine.
So my question is, can I go back to Swift 2.3 on my XCode 8 and still run it on iOS 10?
Also, they told me my app didn't look "good" on iPad since even though I don't support it, it should be playable either way. That was an easy fix but, now iOS 10 doesn't support iPad 2 anymore nor iPhone 4 & 4s. Starts from iPhone 5 & 5s + iPad Air 2.
Should I forget about those old devices now (iPhone 4 and iPad 2) ?
Thanks in advance.