I don't think even a killer feature would help that much at this point, due to the lock-in iOS and Android have at this point, in the form of enormous app catal

I don't think even a killer feature would help that much at this point, due to the lock-in iOS and Android have at this point, in the form of enormous app catalogs. If they had the current Windows Phone with a killer feature or 2 around when the Verizon Droid came out, then they might have taken the market instead of Android, but I think it's too late now. They're doomed to a ~10% or so market share for the foreseeable future, much like Apple was in the 90s, and for pretty much the same reason, interestingly enough.