A Privacy Analysis of the HTML5 Battery Status API [pdf]
eprint.iacr.org
eprint.iacr.org
Main use-case I believe was FirefoxOS -- at least the first time I heard it mentioned was during an FirefoxOS talk where they discussed other hardware-y APIs and trying to get them standardised.
It would also be useful for an OS that supported HTML5 native apps. Additionally having a standard API gives projects like Phonegap an API to 'target' when exposing native device APIs to JavaScript.
- Disable the HTML5 Vibration API if battery power is low.
- Increased network activity is battery is full or charging.
- Project how much time a user has to complete an activity before the battery runs out.
- Change page colour scheme to reduce battery drain.
This is a really useful API - especially if it reduces "range anxiety" for mobile users.
- Network activity should be as predictable as possible, because people often have to pay by the megabyte, and any "smart" changes in activity increase the chance that people will be unpleasantly surprised.
- The OS should predict remaining battery life, not the apps. If there's going to be a new API it should let the apps inform the OS of future activity so the OS can make better predictions.
- Changing color to reduce battery drain only makes a noticeable difference with OLED. It will annoy the more common LCD users for no benefit to them.