I haven't seen other mobile browsers support blocking 3rd party content yet. I think that's mainly because Google is the other major phone manufacturer, and their main source of income is that exact 3rd party content. Apple isn't burdened by that - they want to sell phones and keep them the best. Blocking 7 MB of JS that isn't the content the user wants is a good optimization.
Android supports it in many different forms. If you're rooted you can block pretty much every ad in all apps, but even without root Firefox on Android supports adblocking extensions and there are alternative browsers focused on ad blocking and privacy.
Also to be fair you can already block ads on iOS if you jailbreak your phone.
iOS also has a Ghostery app, but it has a less than optimal user experience. The UI is confusing. They bury essential options in the share icon, options that have nothing to do with sharing.
I'm not sure if the Android version is as bad as the iOS version.
