"App neutrality" or, as it's been more known for years, portability, is a useful thing.
The entire Java language was originally designed as a portable "write once, run anywhere" language although it ran into problems later on, but portability is definitely a useful goal, albeit a conflicting goal with other, also useful, goals.
I'm not sure how "worth it" cell phone app development is anyway unless you already "know" you're going to have the next popular "hit" game. There's royalties involved no matter which smartphone you target and you'd be pretty much just developing for that one phone anyway, where you'd have to repeat for any other smartphones you also wanted to target. Although I believe there are some portable platforms that can target more than one kind of smartphone but I've not looked into it as I'm not a smartphone developer.
But in short, it's not a bad idea to develop some kind of platform-neutral technology that would let people write it once, run it on any smartphones, but by no means does anyone have to do this.
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Okay just read the article and what kind of stupid are Blackberry putting in their pipes and smoking? That had absolutely nothing to do with portability and was some BS trying to force net neutrality to do things it was never intended to do. Yeah but no. No one owes them or anyone special apps just because they say so. If they want the apps they can program them or pay the companies to develop them.
It's like they purposely twist words around and redefine their meaning just to suit them. Whereas "app neutrality" would, to any sensible programmer, refer to portability (platform-neutral i.e. works on many platforms), they twist it around to mean some bogus stuff and invoke net neutrality, also completely out of context. In short, they're calling apples oranges and trying to change laws to do things they were never intended to do.