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BatteryBot Battery Indicator is the original battery indicator app for Android™, released in 2009 as simply "Battery Indicator." Both the free and the Pro versions have maintained a 4.5+ star rating in Google Play from the beginning. It offers two modes: the original status bar indicator and now also a desktop widget. You can use either or both, as you please.
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BatteryBot monitors and shows your battery charge level (percent) as an icon in your status bar, with how much time you have left, temperature, health, voltage, and time since plugged / unplugged in the notification area. It now also has a 1x1 app widget. The Pro version also has user-configurable alarms, logs, mA current information, and a large (4x1) widget.
Give it a try -- it's free and open source! BatteryBot Battery Indicator requires NO special permissions whatsoever. It's an excellent and complete solution to your battery needs.
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Features:
• No ads (why would you want a battery app with ads?)
• Exact battery level in the task bar
• Or hide the task bar icon, keeping notification in tray — or turn notification off completely and just use widgets
• Multiple icon set options
• Automatic time-remaining estimates based on recent usage
• Small (1x1) circle desktop widget
• Notification (with status bar icon) is now optional -- can be used as just a desktop widget
• Very lightweight (please email me if you think otherwise, and I'll help you figure out what's wrong — I promise this app will not drain your battery!)
• Shows 1% increments even on most Motorola devices
• Well-tested and supported on all major versions of Android (2.1 through 7.0; Eclair through Nougat) and form factors (small phones, medium phones, large phones, 7-inch tablets, 10-inch tablets).
• Open source
For those who want more than is offered in the free version, or for those who just like to support small, independent developers like me, the Pro version remains lightweight while packing in many useful features:
Pro-only Features:
• Alarms (fully charged, charge above X, charge below X, temperature above X, or health failure)
• (On devices that allow it) Icon colors (including fully configurable green, amber, red, and black icons)
• (On most devices) Electric current (mA / milliamp /milliampere) reading to/from battery on supported devices
• Large (4x1) desktop widgets
• Battery logging. You can log the battery state (charge, status, voltage, temperature) and browse the logs on the phone or export to CSV.
• Control the notification priority on Android 4.1+ (For example, you can set to "minimum" to hide the icon but keep the notification in the tray.)
• Lots of configurability of behavior and appearance.
• The charging indicator (the bolt under the number that indicates when the device is being charged) for the sets that have it is optional in the Pro version.