Well, we all fell in love with the Galaxy Note 5‘s Screen Off Memo feature when it was launched. Everyone wants this kind of feature on their devices. Few of the users of Samsung having Note 3, Note 4 and Note Edge can have this feature on their devices.
Screen Off Memo, which allows you to jot down a quick note when the screen is off. That means there’s no need to unlock your device. Whenever you have a brilliant idea, just remove the S Pen, jot a quick note down, and save it—it’s that easy.
A developer on XDA forums have created an apk which will provide you with the same functionality on your Galaxy Note 3, Note 4 or Note Edge. You can also use this app on Galaxy S6, Galaxy S6 Edge, or Galaxy S6 Edge+.
You need to install the apk by visiting the official thread here.