How to make Mobile Safari open email links in the Gmail app? Is it possible to make a mobile Safari open email links directly to the native Gmail app, rather than open up to Apple's Mail.app?
There is no way (yet) to change that without jailbreak tweak. Apple forces you to use Safari and (in this case also) Mail.app.

You can find the tweak here: http://www.webpronews.com/jailbreak-tweak-lets-you-make-chrome-your-default-ios-browser-2012-06