Terms

Last updated: 10 August 2026 · WattMate 1.0 for macOS

1. Who you are dealing with

WattMate is made and licensed by Vitali Staradubau, trading as WattMate, tax number (NIP) 5252950301, contact [email protected].

Keys are sold by Lemon Squeezy as merchant of record — they are your seller for the purchase itself. These terms govern your use of the software; see Refunds for the purchase side.

2. What the licence allows

Buying a key gives you a personal, non-exclusive, non-transferable right to run WattMate on two Macs you use. You may reinstall as often as you like, and you may move the licence to another Mac by choosing “Deactivate on this Mac” on the machine you are leaving.

The two plans differ in one thing only: how long the key lives. The yearly plan runs for a year and renews until you cancel; when it lapses the paid parts lock again, and everything the app measured stays on your Mac. The one-time plan is paid once and the key does not expire. Neither plan buys updates — those are not sold separately, and a new version works with the key you already have; see section 5.

You may not resell, rent, sublicense or publish your key, or use one key to serve other people's machines. Nothing here limits what the law lets you do anyway, including making a backup copy and studying or decompiling the program for the purposes the law allows.

3. Free use, and what the key unlocks

The app can be used without a key. What a key unlocks is stated on the front page and does not change retroactively: the projection of watts into minutes, the depth of the run journal, the archive of nights, the totals for the week, month and all time, the per-app page for a period, our own series of battery capacity readings, and the history of quit receipts. The list of apps and their watts, the last run and the most recent night stay free.

The trial lasts ten days, and the clock starts the first time you open WattMate's panel while the Mac is running on battery — not when you install: until then there is nothing to measure and nothing is spent. It starts by itself, asks for no card and creates no account.

4. How the key is checked

This is part of the product, so it belongs in the terms rather than in a footnote. When you activate a key, the app sends it to the licence service together with the name of your Mac, so that your two activations can be told apart. After that it re-checks the key when the app starts and no more than once a day.

A network failure does not take your licence away: only an explicit “not valid” answer does, so the app keeps working offline. A subscription that has passed its renewal date closes locally after a week of grace, without asking the server. A key entered for the first time while offline cannot be activated — it is kept and activated by itself once you are online.

5. Updates

We supply the updates needed to keep the app working as described here — including the changes that new versions of macOS require — for as long as you can reasonably expect for software of this kind, and in any case for the whole of a paid subscription period. Updates are not gated by the licence: a version you download works with the key you have. The app checks this site for new versions and tells you when one has appeared; nothing is installed until you say so. Whether it checks at all is a switch in Settings, and whether a found update installs itself is a checkbox in the update window — off unless you tick it.

6. What the app needs

A Mac with Apple silicon (M1 or later) and macOS 15 or later. The release is built for Apple silicon only and does not launch on Intel Macs. The app is signed with an Apple Developer ID and notarized by Apple. It runs outside the App Store sandbox, because reading another process's energy is impossible inside it, and it asks for no system permissions beyond notifications, which it requests only when it first has a banner to show.

7. What we promise about the numbers

Two things are measured rather than guessed: how fast the battery loses energy, and how much energy the chip uses. Who spent it, and what quitting an app would give back, are worked out from those two. Where the working-out stops is written down in full at How we count, and that page is part of what we promise: if it says a figure is approximate, we are not claiming it is exact.

WattMate is a measuring tool, not advice. Do not rely on it as the sole basis for a decision where being wrong is expensive.

8. Liability

To the extent the law allows, the software is provided as it is, and we are not liable for indirect or consequential loss, lost data or lost profit. Nothing in these terms limits liability for death or personal injury caused by negligence, for intentional harm, or for anything else that cannot be limited by law.

If you are a consumer, your statutory rights are untouched by this section — including your right to have digital content that does not conform to what was promised brought into conformity, or to a price reduction or refund if it cannot be.

9. Ending the licence

You can stop using the app at any time; deleting ~/Library/Application Support/WattMate removes everything it has measured. We may end a licence if a key is shared publicly or used to circumvent the activation limit, and in that case we refund the unused part of a subscription.

10. Law and language

These terms are governed by Polish law. If you are a consumer, this does not deprive you of the protection of the mandatory rules of the country where you live. The English text is the binding one; any translation is a convenience.

11. Changes

We may change these terms for future purchases and for new versions of the app. The terms that apply to your purchase are the ones published on the day you bought, and the date at the top of this page tells you which those were.

12. Trademarks

WattMate is not affiliated with, endorsed by or sponsored by Apple Inc. macOS, Mac, MacBook and Apple silicon are trademarks of Apple Inc. Application names and icons shown in screenshots belong to their owners and appear only to illustrate what the app displays on a Mac.