I discovered one problem that visually impaired people have when using a Android tablet is that they lack any guidance as to where the 'key' locations are on the tablet. Even though the accessibility option in Android speaks the location when your finger is touching a key it is not enjoyable to fumble all over the screen listening to keys you don't want to hit. I developed a simple solution. I used a paper punch and the the thin foil duct tape found in most hardware stores in order to make tactile feedback at the edge of the screen areas. so if you are visually impaired you can easily feel your way to the menu buttons. Easy Peasy! I put a matte screen protector on first (not so Easy Peasy). The bottom line is that it works fine. I can close my eyes and feel my way right to the 'Home' or other buttons. Please notice the slight offset to the 'All Apps' button in the middle on the right. The following photo shows it in use under a CCTV camera.