Privacy Policy

Overview

ThunderVolt runs locally on your Mac. Everything it measures about your battery is processed there and stays there. It reaches the network in only three situations: to check whether your subscription or trial is valid, to see whether a newer version has been released, and — if you turn it on — to sync through your own iCloud account. Each of those is itemised below. We do not run advertising networks, sell data, or track your usage, and there is no analytics or telemetry in the app.

What We Collect

ThunderVolt collects the minimum data required to operate its features:

• Battery telemetry: charge level, cycle count, health percentage, temperature, and power draw are read from your Mac's System Management Controller (SMC). This data never leaves your device unless you enable iCloud sync.
• Charging preferences: your configured charge limit, mode (Storage, Normal, Full), and schedule are stored locally in ~/Library/Application Support/ThunderVolt/.
• iCloud sync (Advanced plan, optional): if you sign in with Apple ID and enable sync, your preferences and anonymized battery health trends are stored in your personal CloudKit private database. No one at ThunderVolt can read your CloudKit data.
• Subscription check: to confirm your subscription is active, the app sends the email address you purchased with to our licensing server, which checks it against LemonSqueezy. Nothing else about your Mac is included.
• Free trial: starting the trial sends a salted SHA-256 hash of your Mac's serial number. We never receive the serial itself, and the hash is used for one thing: making sure one Mac gets one trial. No name, no email, no device name.
• Promo codes: redeeming a code sends the code and that same hash, for the same reason.
• Update check: once a day the app fetches a small version file from our CDN to see whether a newer release exists. It is an ordinary web request for a static file and carries nothing about you.

What We Don't Collect

• No analytics, crash reporting SDKs, or telemetry beacons
• No advertising identifiers or cross-app tracking
• No payment information — card details are handled entirely by LemonSqueezy and never reach us or the app. Your email address is used only to verify an active subscription, as described in §02; we store no name and no device name.
• No browsing history, keystrokes, or clipboard contents

iCloud & CloudKit

The Advanced plan uses Apple CloudKit to sync your settings and battery trends across your Mac, iPhone, and Apple Watch. Your CloudKit data is stored in your private iCloud container. ThunderVolt has no server-side access to it. Apple's iCloud privacy policy applies: apple.com/legal/privacy.

Sign in with Apple

ThunderVolt uses Sign in with Apple for account authentication on iOS and watchOS. Apple may share a private relay email address with us for account recovery purposes. We do not use this email for marketing.

License Verification

To unlock Pro features, the app sends the email address you purchased with to our own licensing endpoint, which runs as a Cloudflare Worker. That endpoint checks the address against LemonSqueezy and answers yes or no. Starting a trial or redeeming a promo code sends a salted SHA-256 hash of your Mac's serial number to the same endpoint, so that one Mac receives one trial.

Two processors are involved, and these are the only third parties that receive anything:

• Cloudflare operates the endpoint and its database, which stores the hash and, for subscription checks, the email address. As with any web request, Cloudflare also processes your IP address in transit. Cloudflare's privacy policy.
• LemonSqueezy is our merchant of record and holds your purchase and payment records. Card details go to them directly and never reach us or the app. LemonSqueezy's privacy policy.

Under the GDPR an email address is personal data, and so is a hash tied to one device — it is pseudonymised rather than anonymous. Both are treated as such here.

Data Retention & Deletion

All local app data is deleted when you uninstall ThunderVolt (the app removes its support files and LaunchDaemon on uninstall). To delete your iCloud data, go to System Settings → Apple ID → iCloud → Manage Storage and remove ThunderVolt.

On our licensing server, retention differs by record and we would rather state it plainly than round it off:

• Rate-limiting records are deleted automatically after one hour.
• The trial hash is kept indefinitely. That is the whole mechanism: if we deleted it, the same Mac could claim the free trial again, so a time limit would defeat the purpose. It is a hash, it is not linked to your name or email, and you can ask us to delete it.
• Your email address is kept only while it is needed to answer whether your subscription is active, and in a revocation record if a subscription is refunded or expires.

You can contact us at the address below and we will confirm deletion within 30 days.

Your Rights

If you are in the UK or the European Economic Area, the GDPR gives you the right to ask us for a copy of the personal data we hold about you, to have it corrected or deleted, to restrict or object to how we use it, and to receive it in a portable form. You also have the right to complain to your national data protection authority.

In practice there is very little to request — an email address and a hash — but the rights apply all the same, they cost you nothing to exercise, and using them will never affect your subscription. Write to privacy@thundervolt.app and we will respond within 30 days.

Children's Privacy

ThunderVolt is not directed at children under 13. We do not knowingly collect personal information from children.

Policy Changes

Material changes will be posted on this page with an updated effective date. Continued use of the app after changes constitutes acceptance.

Contact

Questions or data requests: