Apple
Maybe Steve Jobs saw that oxymoron developing, too. Apple has now relaxed some of its more infamous restrictions on what you can publish in the app store, and what tools you can use to create your applications. Adobe Systems
But I would posit that Google
The App Store rules are still fairly restrictive when compared to the Android market (though Android's store has plenty of other problems). Then again, I guess that's the price you pay for quality control. Apple's app store is still three times larger than the Android equivalent. Microsoft
All of these competitors would do well to copy what Apple is doing right -- which now includes clearly defined and published rules for what your apps can and can't do. But seriously, Steve, how much would it really hurt to allow Flash to run on Apple's hardware?