A few months ago, Google announced its newest flagship device, the Nexus 6, alongside the Nexus 9 tablet and some other sweet news (Lollipop!) Unlike previous phones in the Nexus line, the Nexus 6 featured some very impressive specs that pleased many users–though others were undoubtedly a bit less pleased with its higher price point. One particular feature that ended up in the Nexus 9 but not the Nexus 6 is double tap to wake.
If you happen to own the device codenamed shamu, then you might know that it was actually originally intended to have this option enabled by default. Unfortunately, it was disabled prior to release. Fortunately, it can be enabled back from the shell (using a terminal emulator or the ADB shell) assuming you’re rooted. That being said, if you prefer a simpler method, you’re also in luck: XDA Forum Member naxir made an application that does all of the work for you.
Doubletap to Wake Enabler allows you to enable the double tap to wake feature on your Nexus 6 with a single tap–get it? It also has the option to re-enable it on every boot, and is open source if you’d like to check it out yourself. While the application would normally cost you $0.99, naxir was kind enough to provide a complete APK to XDA users for free. (Note that you still need to be rooted in order for this to work.)
Keep in mind that this implementation was likely disabled in the future because it’s not completely ready for the average user, and may not be entirely reliable if your device has been sleeping for a while. Nevertheless, you’re more than welcome to give it a shot, and see how well it works for you. To do so, simply head over to the Doubletap to Wake Enabler forum thread, install and enable the application!