BattAI: Battery Health

Because iOS does not give any third-party app your maximum capacity or your cycle count. There is no public API for either value, and the private system interfaces that expose them are blocked in the App Store sandbox. Any app that claims to read them automatically is either estimating and presenting the estimate as a measurement, or using something it should not.

BattAI asks you for them once instead, and it takes about two seconds:

• Maximum capacity — Settings › Battery › Battery Health & Charging.
• Cycle count — Settings › General › About (shown on iPhone 15 and later).

Enter them in BattAI under More › Calibrate. From that point on, BattAI tracks everything else on its own and uses your entry as the calibrated baseline. If your iPhone does not display a cycle count, use the diagnostics import described below, or leave it blank — the score still works from maximum capacity.

Because iOS has no public API for any of them. There is no supported way for an App Store app to read battery temperature, terminal voltage, or charge current on iPhone or iPad. An app showing you a number like “34.2 °C” or “3.87 V” is displaying an invention, a value copied from a lookup table, or a nominal constant.

BattAI does not print numbers it cannot obtain. Instead it uses the one legitimate heat signal iOS does provide — the system thermal state, which has four levels — and accumulates how long your device spends in each. That is shown as a heat exposure score, and it is labelled clearly as a device thermal state rather than a battery temperature, because those are not the same thing.

The same rule applies to charging power. BattAI classes a charge as slow, standard, fast or very fast based on the rate it actually observed, rather than claiming an exact wattage it has no way to measure.

Because a single number would claim a precision this data does not have. The forecast is a least-squares line fitted to your calibration readings, and BattAI reports the 95% confidence interval around that line. The band widens the further it extends beyond your data — which is exactly the honest picture.

Two consequences follow:

• A forecast needs at least three calibration points spread over 30 days or more. Below that, BattAI shows nothing rather than drawing a line it cannot support.
• The result reads like “about 14–22 months to 80%”. The width of the band is the uncertainty; narrowing it requires more readings over more time, not a more confident-sounding app.

Apple treats a battery as consumed once maximum capacity falls below 80%, which is why that threshold is the target of the estimate.

iOS does not let any app watch your battery continuously in the background. Personal automations in the Shortcuts app can, by waking BattAI for a fraction of a second to record one precise reading. Four automations cover the moments that matter:

To create each one:

1. Open the Shortcuts app and go to the Automation tab.
2. Tap New Automation (the plus button), then choose Charger or Battery Level.
3. Pick the condition — Is Connected, Is Disconnected, Falls Below 20%, or Rises Above 80%.
4. Select Run Immediately, and turn Notify When Run off so it stays silent.
5. Add the action Record battery sample from BattAI, then save.
6. Repeat for the remaining triggers.

BattAI has a guided setup screen under More › Automations that walks through the same steps and shows how much of your day is actually covered by readings. Gaps in coverage are never filled in with guesses — they are reported as gaps.

These automations run entirely on your device. Nothing is sent anywhere.

Your own diagnostic logs contain the real cycle count and full-charge capacity that iOS will not hand to an app directly. You can share one with BattAI:

1. Open Settings on the iPhone you want to analyse.
2. Go to Privacy & Security › Analytics & Improvements.
3. Tap Analytics Data and find a file beginning with log-aggregated — the most recent date is best.
4. Tap the file, tap the share button, and choose BattAI. You can also save it to Files and pick it from BattAI's import wizard.

BattAI reads exactly three battery fields from that file — cycle count, current charge capacity, and design capacity. Everything else in the file is discarded on the spot: never stored, never written to a log, never sent anywhere. There is nowhere for it to be sent, because BattAI makes no network requests at all.

If the file cannot be parsed — the format changes between iOS versions — BattAI tells you and offers manual entry instead. It never fabricates a value.

No. BattAI never uses subscriptions.

• Lifetime Pro — a single one-time purchase that unlocks full history and long-term degradation trends, the replacement-timing forecast with confidence ranges, and the shareable PDF battery health report. One payment, no subscription.
• Report Pack — a smaller one-time purchase for people who only want the exportable PDF report.

There is no recurring charge, no free trial that converts into one, and no advertising. The price you see on the unlock screen is the price shown by the App Store for your region — BattAI never displays a hard-coded price, so what you are quoted is what Apple charges.

Open the unlock screen in BattAI and tap Restore Purchases. The button is always visible, whether or not you have bought anything.

Purchases are tied to your Apple Account, not to a device, so they work on every device signed in to that same account. If nothing is found:

• Check that the device is signed in with the same Apple Account used for the original purchase — a family member's account or a second personal account will not carry it.
• Make sure the device is online, since restoring asks the App Store, not BattAI.
• If you bought through Family Sharing, confirm the purchase is shared and that you are in the same family group.

Still stuck? Write to us at the address below with the Apple Account email used for the purchase and we will help. Refunds are handled by Apple at reportaproblem.apple.com — we have no access to your payment details or purchase history.

Everything BattAI records — battery samples, charging sessions, calibration values, and your settings — is stored locally on your device and nowhere else. There is no account, no server, and no cloud sync inside BattAI.

To erase it: delete the app. iOS removes its entire container, and every reading goes with it. You can also clear stored data from within the app's settings without uninstalling. See the privacy policy for the full detail.

No. BattAI contains no networking code whatsoever — it performs zero network requests, and every calculation runs on your device. The only moment the internet is involved is when the App Store processes a purchase or a restore, which is handled by Apple's own StoreKit, not by BattAI.

The health score is anchored to your real maximum capacity, so it stays locked until you enter that value once (or import it). Estimating it silently would be exactly the guesswork BattAI exists to avoid.

Coverage is the share of your day for which BattAI holds actual readings. It is below 100% because iOS suspends apps in the background — the Shortcuts automations above are what raise it. Where coverage is missing, BattAI reports a gap rather than interpolating. This is also why the estimated cycle count is phrased as “at least N”: a sampling gap can only push that estimate down, never up.

BattAI requires iOS 17.0 or later and runs on both iPhone and iPad, with layouts built for each rather than a stretched phone screen. The interface is available in 50 languages and follows your system light or dark appearance.

Cycle count is shown in Settings only on iPhone 15 and later; on earlier models, use the diagnostics import or leave the field blank.