Direct competition is difficult due to patents among other things. That is very evident in both the desktop OS as well as mobile OS war. Startups are going to have an insanely difficult time trying to get something up without getting sued by dozens of company brewing in this war. And if thats not the issue, certainly licensing fees will be hefty.
But putting all that aside, Apple is great in many ways currently. To do better is insanely difficult in part because no one has a clue what better actually is and hardware is a huge gamble unlike software. This and the above factor makes things difficult out the door. I would certainly love to see another hardware/software company come up to compete, and even one with a more web presence too (something Apple lacks a lot of when you look at companies like Amazon, Facebook, and Google), but I'm not sure I see a reason for such a company to exist at the moment.
Most companies exist because there is an inherent problem that can be done better. I'm not sure I have much to complain with the way things are going as I'm sure many others don't either. Most of the complaints, if any, are Apple EULA or their closed ecosystem, not so much about things that are actually wrong with their products to the point where its a huge pain point.