Go Easy on Your Eyes by Enabling the iBooks Auto-Night Theme in iOS
A bright iPhone or iPad screen can be painful on the eyes, especially while reading in a dark room. With the latest version of iBooks for iOS, however, you can configure the app to automatically switch to the “Night” theme when appropriate, helping to ensure that you won’t end up looking at a glaring white screen in the wee hours of the morning.
iBooks currently offers three “themes,” which change the color of the background and fonts: white, sepia, and night. “White” is the default theme, with black text on a white background. “Sepia” emulates the look of an old book, with brown text on a reddish-brown Sepia background. It’s much easier on the eyes than the White theme, although with lower contrast. As you may have already guessed, the “Night” theme basically inverts the “White” theme, and uses white text on a black background. This makes it great for reading in a dark environment, and offers better contrast than the Sepia theme.
You can always enable the Night theme manually, but in the latest version of iBooks you can also enable a new setting called Auto-Night Theme. This changes your theme from your default (either White or Sepia) to the Night theme automatically. Despite the “Night” name designating the late hours of the day, the switch is based on ambient lighting conditions, not time. If you have Auto-Night Theme enabled, any time your iPhone or iPad’s ambient light sensor detects a dark room, iBooks will instantly switch over to the Night theme and then switch back when light in the room returns, whether that’s due to the sun rising or a lamp being turned on.
Related: Learn how to make all of iOS easier to see at night by enabling the Invert Colors accessibility option.
To enable Auto-Night Theme mode, launch iBooks and open a book. Tap on the display settings button at the top of the screen, which looks like a small and large ‘A’ next to each other. Find Auto-Night Theme and toggle it to On (green). Depending on your current lighting conditions, nothing may happen at first. But the next time the lights go out or the sun sets, your iBooks app will switch you over to the white-on-black Night Theme.
There’s only one caveat: this mode only works for eBooks. As many users know, the iBooks app is also a great PDF manager and reader, but Auto-Night Theme (and themes in general) unfortunately aren’t available while viewing PDFs.