If you're in the habit of using the fancy-pants Chrome Beta to get access to the newest features for your browser of choice, try this handy zoom gesture out. On any desktop page, double-tap anywhere, and on the second tap keep your finger on the screen. Then slide your finger up and down for a quick and easy zoom. It works the same way that the "pinch to zoom" function does, but with a single finger.
The handy gesture was mentioned on the official Chrome release blog. It has been included in Google Maps for some time, and will presumably make it to the standard Chrome build sooner or later. It will only work on desktop-formatted pages; mobile sites that don't zoom don't need it. The application is obvious: it's for using your device with a single hand when trying to get your index finger and thumb on the screen at the same time might be awkward. Those who have one of the newer, larger phones or "phablets" will probably get a lot of use out of this.
Chrome for Android Beta 30 includes a few other gestures for the menu and tab pages, among other things. You can read about the rest here, and hit up the widget below to try out the beta for yourself.
Source: Google Chrome Releases