The iPad 1 is still not supported in the developer tools, and I've found that if I optimize my apps for iOS 9, they won't install on iOS 5. This means I'll have to end iPad 1 support before early next year, because I will want to offer split-screen and other iOS 9 features sooner than that.
So, my current plan is to release the upcoming Set List Maker 4.2 and BandHelper 2.4 in mid-September, with iOS 5 support, and tested for iOS 9, but not offering any features that require iOS 9. I'll release the next few bug fix updates with the same compatibility. But as soon as the new versions stabilize, hopefully by the end of October, I will end iPad 1 support and release the first versions optimized for iOS 9. At that point, you will still be able to run Set List Maker and BandHelper on an iPad 1, but you will receive no further app updates.