Caffeine Tracker & Sleep Time

☕ How many coffees did you have today?
Caffeine Tracker is a lightweight caffeine diary that logs every drink,
estimates how much caffeine is still in your body, and tells you the time
you can safely fall asleep.

No account, no upload — your data lives only on your phone. Free, ad-supported.


✅ Made for you if you…
• drink 2–3 coffees a day and sometimes can't sleep at night
• want to cut down on caffeine
• track health/diet and want caffeine on the same page
• study, work nights, or watch your caffeine timing for exams


🔑 Key features

📝 Fast logging
• 17 built-in presets: espresso, americano, latte, cold brew, energy drinks, tea, chocolate, …
• Custom entry — name and milligrams in one tap
• Today's drink count and total caffeine update instantly

😴 Sleep guide
• Real-time remaining caffeine using a 5-hour half-life model
• "Recommended bedtime" = when remaining drops below 50 mg
• Hour-by-hour caffeine curve, easy to read at a glance
• Clear answer: "you can sleep now" or "in X hours"

📅 History
• Day-by-day intake log
• Lightweight scroll, no clutter
• Delete a wrong entry in one tap

📊 Stats
• Days tracked, total drinks, total caffeine
• Average caffeine per day
• Top 10 drinks
• Daily chart for the last 14 days
• Share by category — coffee / tea / soda / energy / other

🌐 Multilingual
• English / 한국어
• Switch any time in settings

🎨 Light & Dark theme
• App-level dark mode, independent of OS theme
• Comfortable for late-night logging

🔒 Privacy — 100% local
• Caffeine logs are stored only in a local SQLite database on your phone
• No server upload, no account
• Uninstall or tap "Delete all data" to wipe everything


💡 Tips
• Log in the morning, after lunch, before late work — one second each.
After a week, your caffeine pattern appears naturally in the Stats tab.
• The Sleep curve makes it obvious how long that "3 pm latte" actually lasts.


⚠️ Notice
• The half-life and threshold used here are general estimates. Your real
metabolism varies with body, medication, pregnancy and caffeine sensitivity.
Do not use this app as medical advice.
• Not directed to children under 14.


📮 Contact / Feedback
• Use Settings → Contact to email us
• Email: tk32189@naver.com

★ Small habits, real difference. Log your first cup today! ☕