How to get the Note 5's Screen Off Memo functionality onto the Note 3, Note 4 & the Note Edge.

You do not need to be rooted and this doesn't affect your warranty status.

*To enable the app to lock the screen when spen is attached, you must activate/enable it in Settings-Security-Device Administrator.

http://forum.xda-developers.com/galaxy-note-3/themes-apps/app-screen-off-memo-t3196790