Your sibling comment mentions that Google depends for 90% on search (and webpage) advertisement. For Apple, the iPhone was 65% of their revenue in the last quarter, but the remaining 35% is divided among other products (with some dependency of 'services' on iPhone).
It's still not healthy, but their bets are spread quite a bit better than Google's.
(I think there is quite a bit of monetization potential for Google in Google Apps and Chromebooks. They could move to a position/market that Microsoft was in. But it takes time to grow that business.)
My question is more about the process. Everybody knows that Apple does a lot of internal R&D that never sees the light of day. For example, the heavily rumoured Apple TV.
My question is: do they do a small number of internal R&D projects, or do they do a large number that gets continuously filtered?
Apple approaches R&D a bit differently than Google does. Apple sees R&D as primarily a means to achieve operational efficiency and/or supplier independence. Product development is driven by customer needs and is tightly controlled at the executive level.
Apple likely has a half-dozen products sketched out that they can't release until some technology / market hurdle is overcome. So they focus their R&D on the technology hurdles, and their lobbying/PR efforts on the market ones.
Primarily indirectly, by keeping users on its advertising network. Its 30% cut of Play Store sales has been estimated to be worth ~$10 billion/year [1].
They missed the boat on office in the cloud... Despite nearly a decade of lead, they've essentially lost the GoogleDocs vs Office 365 battle. Google Docs hasn't really moved the needle in almost ten years, while Microsoft's offering is almost as good as the desktop version.
It's still not healthy, but their bets are spread quite a bit better than Google's.
(I think there is quite a bit of monetization potential for Google in Google Apps and Chromebooks. They could move to a position/market that Microsoft was in. But it takes time to grow that business.)