The requirements to be able to use this module similar to Knock code will have root privileges and have installed Xposed Framework, an application that allows us to completely change the appearance of our device through downloadable modules. In the event that you still do not know this fundamental app for those who want to fully customize their phone or tablet, you have a video tutorial that will help you install it easily. After this, we will look for the module developed by an XDA member named Knock Code (while screen on). As the name suggests, this gesture unlock works with screen on and not turned off as with the original Knock Code, so we will need to press the unlock button on our terminal to use the application.
On the other hand, it is also necessary that the unlocking method of our Android is that of the 3 x 3 grid, so if you do not have it already configured, you must change it in Settings -> Security. After restarting and activating the module, we will have ready our Knock Code unlock with a 2 x 2 grid whose default code will be 1234, that is, upper left, upper right, lower left and lower right square.
Obviously we can change the code in the application to make it more secure, although as indicated in the XDA forum, from a security point of view, this way of unlocking is not the safest we can use. Due to how Xposed works, the file where our code is saved can be read by any user, so we don’t need to be root to read it. That in turn means that any app can read the code and therefore know the unlock pattern.
One of the options to reduce this problem is to disable USB debugging since, although the password is encrypted, it will be more difficult to read our code. The Knock Code module is available for terminals with Android 4.4, 4.3 and 4.2 and you can find all the corresponding information in the xda thread. If you are interested in these little tricks, don’t forget to take a look at our dedicated section.