The best alternatives to Battery Watcher are FIPLAB, Battery Indicator, and AlDente. If these 3 options don't work for you, we've listed a few more alternatives below.
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AssemblyAI— The most accurate API for conversational speech-to-text
FIPLAB is an award winning application development studio in London that specialises in creating intrinsically viral, high quality iPhone, iPad, Mac and Windows 8 applications.
Greenify help you identify and put the misbehaving apps into hibernation when you are not actively using them, to stop them from lagging your device or leeching the battery, in a unique way! They can do nothing without explicit launch by you or other apps, while still preserving full functionality when running in foreground.