Interestingly I took a look at Google just a few weeks ago...

Google has three important things going for it:

1 - a single mission - >91% of revenue is from advertising
2 - dominance (monopoly) - Google has 70% market share for web-search (Microsoft 20%, Yahoo 10%)
3 - Advertising is a huge market that is migrating on-line

Also, by partnering with hardware manufacturers [Samsung, LG etc] it is trying to keep in front of the users and be the entry point of choice. iOS has 43% market share but Android has 49%.

The trajectory is onward and upward!

Happy to throw out some other opinions but that about captures it for me...