That's why you need a kick-ass Android browser, and the best you can do in the iOS walled garden: pouring your marketshare from desktop to mobile as much as you can, without threatening actual OS makers. Mozilla are not (or should not be) interested in setting standards for device drivers, so they don't need any marketshare at that level.
To be honest, I think they've finally realized that the OS was a pipe dream -- the iOS release could have happened years ago, but now it's finally been sanctioned. Coincidence?
Getting marketshare on Android or iOS is very hard though: there's some real argument that you will never have enough influence there to make any difference. Certainly trying to get people to install alternate browsers seems harder on mobile OSes than desktop ones.
To be honest, I think they've finally realized that the OS was a pipe dream -- the iOS release could have happened years ago, but now it's finally been sanctioned. Coincidence?