Volt Battery Health Widget

Volt shows your battery's real health, meaning how much capacity it has left compared to when it was new, right next to the charge level you already see.

Most Android phones do not show you this, Oppo, OnePlus and Realme among them. Some builds and some models do include a reading somewhere, but unless yours is one of them there is no way to tell. Volt works it out from your phone's own charge counter, by watching how much charge actually moves in and out of the battery as you use it.

MEASURED, NOT GUESSED

Volt does not invent a number. It watches real charging and discharging and only reports a health figure once it has enough evidence to stand behind one. Until then it tells you it is still measuring.

If your phone does not report the charge counter Volt needs, it says so plainly rather than showing you a made-up 100%. A dash beats a confident wrong answer.

You can open the measurement log and see every reading that fed the figure, so you can check the number rather than trust it.

NO CALIBRATION RITUAL

Volt never asks you to run the battery flat and charge it to full before it will tell you anything. It measures from the swings you already have: a drop from 80% to 40% is plenty, and it reads a discharge just as well as a charge.

That matters if you look after your battery. Keeping it between roughly 20% and 80% is the single best thing you can do for its lifespan, and Volt is built to measure batteries that are treated that way, instead of asking you to stop.

WHAT YOU GET

- Battery health as a percentage, with estimated and design capacity in mAh
- Charge level, temperature, voltage and current draw
- A measurement log showing the readings behind the health figure
- A battery care report that reads your phone's own charge limit setting
- Five home-screen widgets: two gauges (3x3 and 2x2), two bar layouts (4x2 and 3x1), and a single-cell mark that fills up to your health reading

FREE, AND WHAT COSTS

The app is free and the battery health reading is free forever. You can watch the figure appear over a charge, open the measurement log and check every reading behind it, without paying anything.

The five home-screen widgets are a one-off purchase, shown in your own currency on Google Play. Not a subscription, and nothing expires. That order is deliberate: you get to satisfy yourself the number is real before deciding whether it is worth putting on your home screen.

PRIVACY

No ads. No trackers. No analytics. No accounts. No data collection.

Everything Volt measures stays on your device and is never uploaded. The only server Volt ever contacts is Google Play, and only to check a purchase.

HOW IT UPDATES

Widgets refresh on the schedule Android allows background apps, and more often while charging. They are not second-by-second. An always-on battery monitor would cost you more battery than it could ever save you, so Volt does not run one.

A NOTE ON ACCURACY

Health is worked out from how far the charge level moves against the charge counter, and Android reports the level only to the nearest 1%. Wider swings measure more accurately, so a long discharge tells Volt more than a short top-up, and Volt weights them accordingly. Give it a few days of normal use and the figure settles.