What do you mean by market share. AAPL represents ~11% of global market share whilst being bigger than all other tech companies combined. AAPL has some much cash on hand that they can simply buy innovation through other companies as they have done with their myriad subsidiaries.
Nokia corners 49% of global phone sales and they are like Pluto next to the sun when compared to AAPL.
Time will tell lol Apple's PE ratio has been up and down. Only up when they release the next model. I don't see them grow much with their current products. But it's not bad at all. As long as there is no company coming up with new innovative product, they can keep their market share like Nokia did 10 years ago lol.
At least, I wouldn't buy Apple stock. With no future growth, it's a kind of overvalued stock ...