Caffeine Health

Caffeine Health is a beautifully designed Android app that helps you understand how your caffeine intake affects your body throughout the day — and whether that late-afternoon espresso might cost you sleep tonight.

Log drinks from a curated catalog, watch your active caffeine level in real time on a 24-hour curve, and get a personalized sleep forecast based on your unique metabolism.

<b>Features:</b>

• Real-time 24-hour caffeine curve with emoji drink markers
• Personalized pharmacokinetic modeling based on age, weight, lifestyle
• Sleep forecast — see if caffeine will affect your bedtime
• Curated drink catalog: coffee, tea, energy drinks, soda
• Drink detail sheets showing individual contribution curves
• Quick actions — edit, duplicate, or delete entries
• Material 3 Expressive design with dynamic color
• Montserrat typography and haptic feedback throughout
• Full dark mode support

<b>Privacy:</b>

• Fully offline — all data stays on your device
• No ads, no tracking, no analytics, no accounts
• Open source (GPL-3.0)

<b>Science:</b>

The app uses a one-compartment oral pharmacokinetic model with personalized half-life calculation. Your caffeine metabolism is estimated from age, weight, smoking status, alcohol intake, and CYP1A2-inhibiting medications — grounded in real pharmacology.

• Fix a crash on launch affecting some devices and custom ROMs (splash screen exit)
• Time zone now follows your device automatically as you travel (new "Match system time zone" option, on by default; turn it off to pin a fixed zone)
• Cleaned up wording in Caffeine Coach messages

Includes everything from 2.3.0:
• Caffeine Coach: the smallest, best-timed dose suggestion under your home chart
• Type exact fractional serving amounts (e.g. half a soda)
• New Pulse Cup app icon, Material You themed