Appstore revenue importance is way way over-rated. All it shows is that it gives game developers an avenue to make money (since most of revenue came from games) and Apple to feed off this gravy train. Maybe kids/teenagers spent more money in Appstore but the number of affected users/buyers maybe numbered a few tens of million. Compared this to the hundreds and hundreds of million of users for "essential" free apps (e.g. google,fb,tw,whatsapp etc) which you never pay a single cent upfront. But the indirect revenue (gained by the companies that made these so-called free apps) is in the order of hundred of times more than Appstore revenue.
You got it all reversed. Appstore revenue (or other similar indicators) is never really compelling but market share is. There are so many indirect industry-wide benefits that market share gives which are not apparent. If you can't maintain market share only means you go into obscurity into the future. Once a upon a time a huge proportion of smartphone market share/profit was attributed to Nokia (using the Symbian platform). It all went downhill for Nokia when it lost its market share to Apple/Android over a period of time. Will iOS go the same way as Nokia (symbian)?
Yes.... it all went downhill for Nokia when people stopped buying Symbian phones and started buying other phones. When you aren't selling phones... that's when you get in trouble.
People ARE buying iPhones though. Apple is still the #2 smartphone manufacturer by volume. And they make a lot of money on every phone they sell.
The thing about market share is... it's a percentage. It's based on what everyone else is selling too.
But every company is responsible for themselves.
Over the Holiday quarter... Apple only had 18% market share... but they happened to sell 51 million smartphones. Their highest quarter ever.
The market share was calculated after the analysts tallied up everyone's phone sales. But Apple sales are theirs... and theirs alone.
What if someday Apple's smartphone sales "drop" to 12% market share... but they sell 60 million phones? That's entirely possible... and I don't think that will force the iPhone into obscurity.