Strange
I find your post very strange and the idea behind it looks clearly wrong and even nonsensical. If you look at the results of your post, you will find that only a small amount of members share the same view.
Despite that, threads like this just keep being created. I bet that you can't name a single innovation (consumer level) from Apple's competition since 98, not to mention those desperate measures that dying corpses like Blackberry, HTC, Nokia, Sony, LG, Dell, HP and Motorola are taking to appear relevant (The amount of money they lose says otherwise). They offer 0.
On the other hand Apple isn't investing on iPhones, they are investing on an ecosystem. That ecosystem of costumers buy close to 100 million iOS devices each quarter, high end devices. Every decision must be extremely analyzed.
Apple could easily put a 4k screen on an iPhone right know. However, could they master those processes so they can sell north of 50 million each quarter? No one has that problem. I mean, LG sold less than 2 million G2s last quarter, Nokia only sells Lumias 520 and even the 5c outsold the Galaxy S4 last quarter.
Where's a bigger screen for the iPhone, you might ask. I also agree that Apple is milking it for too long, but software limitations existed (now we have the texture free iOS 7) and as apps support iOS 7, those problems become something of the past. However, being ignorant about the situation never helps.
But my point is: We are in a situation where most competitors are in extreme trouble, Samsung sells more devices (especially low end) because they have deep pockets for marketing and are vertically integrated (they own their country) and not one important innovation comes from them. So, I ask:
Why is Apple forced to innovate? Why this strange "Apple must innovate or die (but they will die soon after anyway) mantra?
Apple is doing great, better than everybody else. Saying otherwise is being ignorant and wrong. You can bet that they will stay around decades more than the Dells and HTCs of this world.