This is the upmost best app I have ever seen in my entire life. I work in the dark so I'm actually having an extremely hard time adusting or focusing my eyes on anything closs up, as of recently. Not only that, my eyes aren't itchy anymore thanks to this app. The best feature of this app is the fact that I don't have to exit out of any apps to adust the dimmer. I can access it all from the notification bar. This dimmer makes your screen so dark when you put the level of darkness on 100% so don't forget to turn the dimmer off before your sleep, or else you'll have a hard time trying to turn off the alarm clock on your phone *knows from experience.*