Hydration, honestly. Meet Lottie.
A water tracker with a firefighter bottle for a mascot, real caffeine pharmacokinetics, and zero guilt-trips. Bedtime predictions, no login required. The truth, never the alarm bell.
The Sip difference
is in the maths.
Track caffeine, not panic.
Most hydration apps ignore caffeine or treat it like a sin. Sip does neither. Your caffeine onboard is modelled with real pharmacokinetics, a standard 5-hour half-life, so the only question that matters has an honest answer: can I sleep tonight?
half-life
now · ramping
unaffected
The curve doesn't lecture. It just decays.
Two trackers, one app.
One honest number.
Your year, at a glance.
Goal-hit percentage, longest streak, last 30 days as a calm line graph. The proof Lottie is doing her job, or you are.
Day. Week. Month.
Your day as a clock-dial. Your week as bars. Your month as a streak map. The same data, sliced however your brain wants it.
Light by day, dark by night.
Diagonally split, both finished. The bottle still fills, Lottie still salutes, whichever side of the day you're on.
Hi, I'm Lottie.
Part bottle, part firefighter, all hydration accountability.
"Psst, wrong mug? Tap it. I won't tell. I also don't make the rules; I just shout the milligrams."
Sixty seconds to set up.
Then the maths runs itself.
Set up your cups.
Bottle, mug, can, sports flask: the actual vessels you drink from. Your daily goal tunes itself to your body and the weather.
Tap to log, not type.
One tap on the cup chip and you're logged. Or skip the app: home-screen widgets and the Wear OS tile log a cup in one tap.
Watch the curve.
Caffeine onboard updates every minute, with peak and clearance on one chart. About to order another? Sip shows the new bedtime first.
Things Sip will never do
to your day.
Won't ping you at midnight.
If you missed the goal, it's tomorrow's problem. No notifications between 22:00 and 06:00, full stop.
Won't lock the maths behind a paywall.
The caffeine model, the bottle, the cup catalogue, today's numbers: free for everyone. Pro adds depth; the science is never gated.
Won't pretend coffee is a hydration crime.
It isn't. We model it like a chemist would: exponential decay, real numbers. The truth, not a lecture.
Won't sell your data to a wellness brand.
No account, no email capture. Your logs live on your phone, with Android auto-backup to your own Google Drive if you choose. Ads respect your consent choice; Pro turns them off.
Won't gamify away your self-trust.
Streaks exist and Lottie celebrates them, but the headline number is your 30-day average: calmer, and harder to fool. Streak freezes catch you on rough weeks.
Won't ask you to weigh your food.
This is a hydration app. If you wanted a calorie tracker you'd already have one, and you'd already be tired of it.
Less ads. More depth.
Same honest maths.
Sip, on autopilot. Pro turns ads off, unlocks unlimited history, backfills past days, keeps your goal tuned via Health Connect and surfaces weekly Pro Insights. The free version stays fully featured. Cosmetics are sold à la carte, never bundled.
Things people ask
before installing.
What's Sip Pro?+
A subscription that turns ads off, unlocks unlimited history (free keeps the last 30 days), backfills past days, syncs with Google Health Connect, hands out unlimited streak freezes, and surfaces weekly Pro Insights. Monthly or annual; prices live on the store listing. The core trackers stay free with no time limit.
Where does the 5-hour half-life come from?+
It's the average elimination half-life for caffeine in healthy adults, well established in pharmacokinetic literature. Individual half-lives vary (1.5h to 9.5h). Sip uses the population average and lets you adjust it if you metabolise caffeine fast or slow.
Is the app actually free?+
The free tier is real and useful: log water and caffeine, see today's curve and your bedtime prediction, set up custom cups, log from widgets or your watch, browse 30 days of history. It shows ads that respect your consent choice; Pro removes them and adds depth. The maths, the bottle and Lottie are never paywalled.
Will there be an iOS version?+
Yes, it's in the works. Sip's maths is moving to a shared Kotlin core so the iOS app can be fully native SwiftUI. Android ships first; join the waitlist and we'll tell you when TestFlight opens.
What does Sip not do?+
It doesn't track sleep, calories, steps, mood, or your menstrual cycle. It does one thing, fluid in and caffeine out, and tries to do it well. (It does have a Wear OS app, because one tap on a watch beats unlocking a phone.)
Why is the mascot called Lottie?+
She's a water bottle who works as a firefighter. "Bottle" → "Lottie." We thought it was funny at 11pm; we still do at 9am. The hose is canon.
Less tracking,
more water.
Free tier with the maths. Pro for depth. Cancel any time.
Know the moment
Sip's ready for you.
Android's in beta, iOS is next. One email — no account — and we'll tell you the second your platform opens up.
