# Kaff — Caffeine Watch — The caffeine still in you

> The caffeine still in you (iPhone/iPad app by NICOLAS HUGO PAUL BATAILLE.)

- Source: https://appshunter.io/ios/app/kaff-caffeine-watch/id6808741325 (this page in markdown: same URL + `.md`)
- Developer: [NICOLAS HUGO PAUL BATAILLE](https://appshunter.io/developer/1896572439)
- Category: Health & Fitness, Lifestyle
- Price: Free
- Age rating: 4+
- Requires: iOS 18.0 · 4 MB
- Languages: French (France)
- Released: 2026-09-30
- Data updated: 2026-10-05

## What is Kaff?

Kaff estimates how much caffeine is still in your body and shows it on your Apple Watch face.

You log what you drink: an espresso, a tea, a cola, or an amount in milligrams. You set the volume with the Digital Crown. If you forgot a drink, you can add it later, up to 24 hours back.

Kaff then works out, minute by minute, how much is left. It uses the standard pharmacokinetic model for caffeine: the level rises for about 45 minutes, then falls according to your half-life, which you can set from 2 to 10 hours.

The main screen shows:
• the current amount, compared with the peak of a 200 mg dose;
• today's total, compared with the 400 mg a day recommended by EFSA;
• what will be left at bedtime, and when you will drop below 35 mg.

The complication shows the level on your watch face and keeps it up to date on its own, without opening the app.

Optionally, Kaff can work out your usual bedtime from the nights recorded in Health. It can also let you know when your level has come down, or when one more coffee would likely affect your sleep.

Entries are saved to the Health app. Kaff has no account, no ads and no server: none of your data leaves your watch.

The limits come from EFSA, the FDA and a 2023 meta-analysis on caffeine and sleep. Every source can be viewed in the app.

Kaff gives an estimate, not medical advice. No sensor measures caffeine: the calculation relies on what you enter, and the real caffeine content of a cup varies a lot from one coffee shop to another. For adults only; not suitable during pregnancy.

## Is Kaff safe?

Not enough ratings yet to assess Kaff.

## Is Kaff legit?

Kaff — Caffeine Watch has limited verification signals. The AppsHunter Legitimacy Score for Kaff is 50 out of 100 points across 7 verification signals from App Store and developer data.


## Version history (last 2 releases)

### 1.0.1 — 2026-10-01

Fixes a crash when opening the half-life setting. Sources can now be opened on your iPhone.

### 1.0 — 2026-09-30

No release notes.

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-10-05.*