Well, then Apple is not worth mentioning in this context: they also started from zero with iPhone, and I'd say even more so.

It would be interesting to know what those disagreeing think. Google had zero market share, but they did not start Android, they bought it and finally released.

Apple had zero market share and developed the OS and the hardware themselves.

What do I miss?

Apple released before Android, and obliterated the market. Apple attacked the incumbents in the phone market at that time, Nokia, rim, palm, Windows. Android then entered the market, and "attacked" all of the incumbents again, which at this time includes Apple. Thus, as the last major entrant, it can be said that Android is fundamentally an offensive against all of the other preexisting platforms.

Similarly with the browser, Chrome is the "latest entrant", the latest challenge to the incumbents of ff, ie, safari, opera.

In each case, being the latest entrant, Google is not in the position of protecting market share from new entrants, they are in position of taking market share from incumbents.

This will change over time, as Google market share matures, and new entrants and or older incumbents make moves, but for now, as the latest major platform introduced, it can be said Google is acting in an offensive manner from each markets point of view. I think rather than "starting from zero" alone, the real context meant was "most recent to start from zero".

  > the latest challenge to the incumbents of ff, ie, safari,
  > opera.

To be fair, market share of Safari and Opera (in the west at least) were not and are not something to brag about.

To your original point, Apple's WebKit didn't come from nowhere either. It was a fork of KHTML from the KDE project.

Where do you see the that point? Did I claim Apple started with Safari from zero? I did not.