The HTC One M8 came not just with improved hardware but some interesting new software features as well. One of those is gesture-based lockscreen launcher Motion Launch, which can now be enjoyed by almost anyone thanks to an app called Knockr
Given how LG, Motorola, and Samsung, has been marketing gesture-based interaction in their latest devices, it was quite natural to see HTC also attempt to bring in such features. Motion Launch combines gestures, taps, and whatnot to immediately jump to the task at hand. A double tap on the screen will unlock the phone like the early KnockOn days, while putting your phone to your ear will immediately answer an incoming call like Samsung's motion-based actions.
The name might be a bit mislead, but Knockr isn't a Knock Code clone, though it does have something like that. Once the app is installed, users will be able to configure six preset gestures to launch any app of their choosing or unlock the device. All of these gestures only work if the smartphone is locked. By default, a double tap will unlock the smartphone. There is also an option to have Knockr automatically disable itself when it the smartphone is either inside your pocket or bag or faced down on a surface. One action is actually not included in the list and therefore isn't configurable. When the smartphone is held in a landscape orientation, like a camera, pressing the Volume Up button will immediately launch the default camera app.
There is, however, one huge technical limitation to Knockr. It only works on devices that use an OLED displays, like some of Samsung's smartphones and the Moto X. This is due to the fact that OLED allows the screen to technically still be enabled, and thus receive touch events, even while seemingly turned off. Also do note that Knockr "steals" the unlocking feature of the device's physical lock button, usually the power button, so that pressing it won't wake up the display as normal. It still. however, works when locking the phone.