What does the battery saver feature actually do?
I am wondering this myself. I googled for "settings > battery > battery saver" and found a few references.
From the Droid Ultra manual:
"When the battery level is low, your smartphone will prompt you to activate battery saver mode. To manually activate this feature, tap Apps > Settings >Battery >Battery Saver, and tap the switch to turn it ON."
From a discussion about a custom Android 4.1 ROM:
"Id like to see the battery saver option in settings, it droped the clocks down to 1.13ghz without having to use the oc kernel. Was settings-battery- battery saver."
After 31 hours on battery I finally got down to 15% and I was asked if I wanted to turn on battery saver. The pop-up explained that Battery Saver will automatically disable background data when the battery is below 15%. I guess the idea is that you might stop certain apps from syncing, and might stop receiving emails (unless they are a special exception to background data?), but you'll still be able to receive phone calls and texts.
Here's what the prompt looked like in the notification bar and then when I clicked on the notification:
I don't think manually turning this switch on means that it will ALWAYS disable background data (you can do that elsewhere), so the quote from the droid ultra manual is kind of confusing.
Good explanation here. Kind of exactly how it works. As soon as the battery is charged above 15% the saver feature is stopped, and normal background data syncing returns.
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