Sometimes I think there is a general misunderstanding of the word innovation. Apple are not always at the cutting edge of technology but they are able to design new methods to make the current technology work far more impressively than the rest of the market. The hardware may not be innovative but it's how they used it.
Tablets and phones are the best examples both of these were around long before Apple but they were able to put them together in a way that made them far more useful to the average person than any other company.
Yep. Claiming that Apple aren't innovative is quite simply incorrect. They are arguably the most innovative company in their respective fields by quite some distance when you think about it.
They tend to make one big leap with a product category (iPod, iPhone, iPad for example) and then evolve it at a steady pace. That's how they choose to do it and they tend to do a fairly good job.
I don't think they need to offer a single identical iPhone with different screen sizes. It just wouldn't seem right. One handed use is an important consideration when it comes to a phone (remember, it's a phone) and the Android manufacturers tend to not concern themselves with that. They only offer one size when they release a new phone as well.
For example, the Galaxy Mini is basically a rubbish version of the flagship, larger Galaxy phone that exists at the time. It's not a proper alternative. The only situation where this is the case is the Galaxy Note II against the Galaxy S III... and the Note II is pushing it for a phone.