Benedict Evans wrote a characteristically brilliant analysis in What does Google need on mobile? Here’s a taste of his conclusion about Google’s challenge going forward:

The key change in all of this, I think, is that Google has gone from a world of almost perfect clarity—a text search box, a web-link index, a middle-class family’s home—to one of perfect complexity—every possible kind of user, device, access and data type. It’s gone from a firehose to a rain storm. But on the other hand, no-one knows water like Google. No-one else has the same lead in building understanding of how to deal with this. Hence, I think, one should think of every app, service, drive and platform from Google not so much as channels that might conflict but as varying end-points to a unified underlying strategy, which one might characterize as ‘know a lot about how to know a lot’.

Don’t miss this article, the whole thing is great.