HTC One User Manual page 47

47 Your first week with your new phone
Using power saver mode
Power saver mode helps to increase battery life. It reduces the usage of phone
features that drain the battery such as the display and data connection.
1. With two fingers, swipe down from the status bar to open Quick Settings.
2. Tap the Power saver tile to turn power saver mode on or off.
If you want to choose which phone features to conserve power for, tap
before you turn power saver mode on.
If power saver mode's Data connection option is selected, HTC One automatically
disconnects from the mobile network after 15 minutes when the screen is off and
the data connection is idle (no download activity, streaming, or data usage). It
reconnects and then disconnects periodically when the data connection is idle to
save battery power.
Keep in mind though that the Sleep mode option for the data connection in
Settings > Power, when enabled, overrides power saver mode.
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