cafein: fun coffee tracker

This app helps you use coffee as fuel and prevent it from costing you sleep. Tap one button to log an espresso, matcha, energy drink, or even a Coca-Cola. A real bi-exponential pharmacokinetics model projects how much caffeine you'll likely still have in your bloodstream when you want to be asleep.

WORK WITH YOUR NATURAL CORTISOL
Cafein shows your cortisol awakening response, the natural alertness curve that peaks in the first hour after waking. Drinking coffee inside that window can blunt how strongly caffeine hits. Cafein highlights the window where your first cup tends to land hardest (typically 1.5 to 3.5 hours after wake).

SIMULATE BEFORE YOU SIP
Thinking about a 4 pm espresso? Cafein lets you test combinations without committing. See how that hypothetical second coffee changes your bedtime number, then decide.

BUILD YOUR HEALTH STORY
Every cup syncs to Apple Health. Your data is yours, exportable as CSV any time, ready to share with your doctor or AI assistant.

WHAT IS INSIDE
- Real-time caffeine gauge with rising indicator
- 24-hour rolling caffeine curve with bedtime marker
- Sleep-impact projection at your set bedtime
- Cortisol-based optimal coffee window
- 10 drink types: espresso, big coffee, green tea, matcha, black tea, mate, energy drink, Coca-Cola, chocolate, decaf
- What-if simulation for combined doses
- Apple Health sync (caffeine intake)
- Edit history, adjust bedtime, fine-tune your half-life

CAFEIN PRO unlocks unlimited logging, unlimited simulations, and CSV export for AI assistants and your own analysis.

Terms of Use (EULA): https://www.apple.com/legal/internet-services/itunes/dev/stdeula/