I am looking for an Android application that can show the battery charging rate (e.g. in mA).
Free is better, but paid OK too.
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Sign up to join this communityBattery Monitor will show that.
It has the ability to show it as a widget as well as in-app. It's also free (with ads)
It's pretty simple to use. I only used it for a short while but it does what you need.
The feature to show charging rate is a free feature.
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CurrentWidget also provides the charging information as a widget, and is also free.
CurrentWidget can also stay in your notifications bar to provide information, as well as provide alerts when the phone is using above a certain amount of power which I liked. Didn't really have any cons about them when I was using them.
Another popular alternative: Ampere.
Measure the charging and discharging current of your battery.
PRO features:
Widgets
Notification
Alerts on device
Alerts on Android Wear
Galaxy Charging Current Free is another app that will show the battery charging rate.
Works on my SGS3.