If you are one of those who like to read on iPad or iPhone during the night, before going to sleep, you know how uncomfortable the brightness of the screen can be in a dark room, especially when you sleep with someone else. Even if you lower the brightness to the minimum that the system allows, the light is still intense when you are in a pitch black environment.
Not everyone knows, but luckily there is a way to make the screen even darker, so that it less obscures your eyes in the darkness.
The trick is to use a feature of the function zoom, present in Accessibility. This function is very useful to enlarge parts of the screen in times of reading difficulties. To make the screen much darker we will use this function to activate a filter called Dim Light, but without actually using the zoom. Follow the steps:
Step 1: Enable zoom
Go to Settings and enter General »Accessibility» Zoom and activate the function. A magnified window will appear.




Step 2: three finger tap
You will now have to give three quick touches with three fingers at the same time on the screen, to appear a new menu of options.

Step 3: Enable full screen zoom
In the same black menu, tap the option Zoom in full screen.

Step 4: zoom out
Still in the same black menu that is on the screen, touch the first option, Reduce.

Step 5: choose the filter
At this point, everything is activated and ready to use. Exit Settings and on the normal screen (or whatever you are on), tap three times quickly with three fingers at the same time. The same black menu will appear in the center and then you will touch the option Choose Filter. Then select Dim Light. You will see that the screen will now be much darker, perfect for reading at night in bed.

To return to normal brightness, simply tap again three times with three fingers, select Choose Filter and then touch none.
Note that this accessibility shortcut is also used for other filter modes, such as inverted colors and shades of gray. If you use the same three fingers to double-tap (not three), it activates the zoom on the screen. The same two taps bring the image back to normal.
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