Interesting thing I noticed... I created a simple app using the iOS SDK which works great! :-)
However, that app then becomes a valid target for 'Open in...' when for instance I tap on a .fmp12 file in my DropBox and tap to open the share sheet and then the 'Open in...' button. FileMaker Go gets listed as usual, and also my custom app... I can choose my custom app and the file opens in it and functions just the same as when opened using FMGo.... Not really surprising considering the custom app basically is FileMaker Go. But I do wonder, is there some setting somewhere in Xcode that I could use to disable my custom app from appearing in the share sheet?