I'm a developer and I think this is a load of rubbish from Apple!
How can some app that is available cross multiple platforms effect the sales of that platform!?
Secondly developers use Unity 3d and others that use X-code to compile the code into an Iphone application these may be effected and the quality of application produced are very high compared to a totally built from scratch solution.
From a developers point of view if I had to code a 3D game engine make the 3D art make all the design and then put that together for one platform (yes maybe the best currently) But I aint gonna do that for speed. This is where Unity comes in!
personally I think that if Apple wanted to be lock down the Iphone development then they should make all these 3rd party compilers use X-code like Unity so every developer still has to use a Mac and X-code.
But just to Kill off all these tools that developers use is absurd.
I guarantee they aren't killing all development tools, not even close.
This is clearly all about maintaining control of their OWN platform and not ceding it to the likes of Adobe. If you think about it in that light, you can get a better handle on what will likely be blocked and what won't.
Tools that aid development for the iPhone platform will be allowed. (libraries used in Xcode projects)
Tools that attempt to be a meta platform on top won't. flash-to-app, or other write once compile many cross platform app generators.
The former offer benefits to the platform, the latter try to supplant it.
How the meta-platform, cross platform app generators damage the platform is clear if you think it through.
1: Lowest common denominator apps. No differentiation. No unique features used.
2: Less incentive to innovate the platform because of (1).
3: loss of control of platform because of (1) and (2)
4: For a platform with approvals, a Tidal wave of mediocre, lowest common denominator apps flooding the approval queues. Meaning longer approval times for all devs, harder time finding quality in a sea of drek.
I want to expand on #4. Because I have seen the ridiculous notion before that there are already mediocre apps using Xcode, so this doesn't matter. There are mediocre Xcode apps, but that doesn't make it sane to open the doors to a flood of more mediocre apps.
But those numbers will easily be TEN(maybe hundred) Times worse once the script kiddies can turn flash into apps.
Adobe proudly declared in one of their Flash-to-App videos that a small handful of pre release users had already dumped more than 100 shovel-ware apps in the appstore. It will be a nightmare for Apple if they didn't block this.
Apple won't lose developers with this move, they would lose more real developers if they allowed the script kiddies to crush the approval queue and flood the appstore with drek.
Apple doesn't need more mediocre apps in the appstore.