Interestingly enough the EU is looking at that. Also, the US FTC threatened to investigate Apple over the "no third-party tools" thing they imposed on develope

Interestingly enough the EU is looking at that. Also, the US FTC threatened to investigate Apple over the "no third-party tools" thing they imposed on developers alongside "Thoughts on Flash". That's why they never followed through and removed it from their App Store guidelines. So there is a limit - somewhere between "technical lockouts" and "we won't approve things made with third-party tools".