While getting hammered by Wall Street and the press for not innovating, they stick to their guns and keep evolving in incremental steps, and laying the ground for the innovation they want to do in the future.
For example, current iPhone battery life isn't the greatest compared to some of the larger phones out there that are packing much more battery.
But they keep making small efficiency improvements, over and over, so that if (when?) release a device with a larger battery, it will be like the MacBook Air situation, where the MBA gets staggering battery life on the next hardware iteration compared to competitors that have just adequate battery life, basically being carried by the hardware.
I imagine the larger display is a similar situation, they're not happy with some compromise they'd have to make to produce a display of the larger size, whereas competitors are happy to pump something out that is better by some metric (PPI, size), but has adverse effects (battery life, color oversaturation, artifacting).
I think Google has the ability to continue competing with them if they remain focused.
I have my doubts about any of the other Android manufacturers, though Xiaomi could be interesting in the future, due to their focus on services.