I am not used to getting 1 star reviews against TV Towers USA. My small niche of RV enthusiasts are usually a happy lot. However, I made the big mistake of pushing an update (I guess the first one was 1.6) which was marked as supporting iOS 5.1 (i.e. the last for the original iPads) without testing against either a device—which I don't own—or the iOS 5 simulator—which Apple no longer provides. And it crashed on first launch, and if it had survived that crash it would have crashed again, and if it survived to finish launching it would have crashed on showing a detail page.
My father, of all people, had an iPod Touch still running iOS 5 that one of my sisters had given him, and he was nice enough to overnight it to me. It's not his favorite device; an iPhone without the phone he calls it.
Crash number one was probably the issue of iOS 5 not handling binaries which include a 64-bit compile. I had fixed that one in TV Towers USA 1.6.2 when I was blindly trying to fix the app.
Crash number two was at the linking stage. My own SVGgh library included a routine to build up an attributed string version of an SVG path and it had included a reference to the NSForegroundColorAttributeName constant string. Which wasn't available under iOS 5 and caused the app to exception out during launch with a symbol not found error. It isn't even used in this app, but the linker doesn't know that.
Crash number three was that some of my xibs were marked to be of the 6.0+ format instead of 5.0+ format.
And crash number four was that the table data source in the tower detail pane was using the category on NSIndexPath that returns an item instead of the archaic row property. This is a bit of syntax sugar made for use with UICollectionViews, so it, of course is not available under iOS 5.
Everyone of these issues was quickly fixable. And I failed my users by not keeping track of my supported OS versions and at a minimum running through the app before overwriting their existing, working copy.
And, I still don't have an iPad running 5.1.1, so I will just have to pray that there is nothing in the small amount of iPad only code with some similar present for me.