I don't understand your point. The iPad has a 130 dpi display, if anything, it should be easier to double that than it was to double the iPhone 3GS's 160 dpi. (I know that making larger displays at that resolution is harder and more expensive, but that won't be an issue forever.)
You've grasped my point better than you realize. As you say the larger screen size and number of pixels outweighs the smaller pixel density.
This does change over time but that's also my point, more heterogeneous rivals can re-purpose various display sizes as required and as time passes they'll get higher res screens before the iPad, just like various iPhone rivals did.
They've also marketed themselves into a corner since even if they double the 130dpi screen they'll not reach their "magical" figure of 300dpi, and they've now introduced pixel density as a marketable commodity in one market, when they're at a disadvantage in another.
Ah, I get it now. I agree to a point. I'd add that once resolution itself is no longer an issue (because every phone's screen is above 300 dpi), Android still has the advantage of custom aspect ratios.
Regarding the iPad, marketing-wise, they might claim that people typically hold the iPad farther away from their eyes than 12 inches, say 15 inches, which places the "retina limit" conveniently just under 260 dpi.
I think you're exaggerating their demise, as it were. iPhone competitors released phones with higher res screens. So what, the next release of the iPhone trounced them all. Now the competitors will release something better and Apple will respond, on and on.
The difference between a Smart phone and a normal phone is it's not as easy to dump your current phone and just move to another. The differences will have to be pretty big to get people to be willing to go through the trouble of learning a whole new phone, moving their data, etc. And I don't buy the carrier argument because from my experience all US carriers are awful.
And having custom resolutions isn't necessarily a win. Look at all the complaining about the different Android resolutions so far. Just wait until they get 5 or 6 new ones.
