In the Google Maps app, you can zoom with one finger by tapping then sliding, like a double-tap but the second touch is a slide. I find this quite useful because I often hold and use my phone with one hand while the other hand is writing/typing/eating/carrying things/etc. So I'm wondering if there is a tweak that enables tap-then-slide up/down to zoom in every zoomable view, or at least in every webview. If there is not, how difficult would it be for me, as someone who has programmed in C/Objective-C/Matlab/a few other languages but never before made a jailbreak tweak, to make it as my first foray into the realm of iOS modding? I've seen a few resources for hooking into the runtime and modifying methods, but if you have any good links/tutorials that would be helpful. Also, if you happen to know what exactly I'd have to make it listen for in order to grab tap-then-slide gestures the "right way", I'm all ears.