Sponge
Automatic sip tracking
On-device sensors log every sip the moment you drink, no buttons, no manual logging, no guessing how much water you’ve had.
Pre-order · Cancel any time before it ships
The smart hydration tracker for any water bottle
Sponge is a clip-on hydration tracking device that automatically tracks your water intake, every sip, from the bottle you already own. Clip it on, drink, and let the app keep you on track to your daily goal.
Works with any bottle8-day batteryFree iOS & Android app
Tracking sips
1.4Ltoday · 78% of goal
100+
Sponge products shipped
30-day
Money-back guarantee
8 days
Battery life
Apple
Health sync on iPhone
Meet Sponge
One tracker. Every sip, counted.
Sponge clips onto the bottle you already carry and quietly logs your hydration all day long.
The problem
You already know you should drink more water
That’s the problem. Reminders get swiped away. Tracking apps get abandoned in a week. Smart bottles start around $80 and ask you to give up the bottle you actually like. Knowing was never the missing piece — consequences were. Sponge is $59.99, clips onto the bottle you already own, and locks the apps you choose until you’ve caught up.
How it works
Clip, sip, repeat
A genuinely passive hydration tracker. Three steps, then it disappears into your day.
1
Clip it on
Clip Sponge magnetically onto any water bottle in seconds. No new bottle, no setup ritual.
2
Sip like normal
Drink the way you already do. Sponge’s sensors automatically record every sip, zero logging.
3
Hit your goal
The app tracks your intake in real time, nudges you when you fall behind, and celebrates your streaks.
Features
Everything a hydration tracking device should be
Effortless to use, impossible to forget, and built around the bottle you already carry.
Clips to any bottle
A magnetic clip snaps onto the bottle you already own, from insulated steel to glass tumblers. No proprietary bottle to replace.
8-day battery
Go a full week-plus between charges, then top up in a couple of hours over USB-C. Charge it Sunday, forget about it.
Free app, plus a widget
A clean dashboard with daily goals, streaks and trends — and an iPhone home-screen widget, so most days you never open the app at all.
Hydration Locks
Choose the apps you lose hours to and set what unlocks each one. They stay shut until the water is actually gone.
Syncs to Apple Health
Your intake writes straight into Apple Health on iPhone, so it sits alongside the rest of your health data instead of stranded in one more app.
Hydration Locks
Water is the password
Pick the apps you lose hours to. Sponge locks them, and they open when the water is actually gone — not when you promise it will be, and not when you tap “ignore”. Every other hydration tracker hands you a number. This one does something with it.
- ✓ Choose which apps to put behind your daily goal
- ✓ Set the amount that unlocks each one
- ✓ They unlock as you drink, sip by sip
Brutal? A little. It is also the reason people are still using Sponge in month two.
On your phone
It lives where you already look
Two things that mean you barely open the app, and your hydration stops being a number stranded in yet another place.
Sponge also writes your intake into Apple Health on iPhone, so it sits with the rest of your health data rather than in a silo.
Who it’s for
Built for anyone who keeps forgetting to drink water
One simple hydration tracker, a lot of people it quietly helps every day.
Athletes & active people
Dial in hydration around training and recovery with accurate, automatic intake data you can trust.
Busy professionals
Back-to-back days make it easy to forget to drink. Sponge tracks for you and nudges before you fall behind.
Caregivers & families
Keep an eye on a loved one’s hydration with effortless tracking and shared progress. See our caregiver program →
Reviews
What early customers are saying
Real, unedited feedback from the first Sponge owners.
“Beautiful.”
Verified customerFocus and energy · Gift for someone
“Still testing it out but the app works well. It would be nice to see a how-to video explaining any nuances, including whether it keeps tracking water intake when the app is closed. It would be cool if it integrated with Whoop or Apple Health.”
Verified customerDaily habit building · Fitness and training
“I really like the clip from a hardware perspective. The main thing I’d love is a connection from the app to Apple Health, and, if possible, not having to open the app to sync data from the clip.”
Verified customerFitness and training · Preventive health
“Needs to be thinner, like 10mm total.”
Verified customerPreventive health
Stop guessing. Start tracking.
Over 100 Sponge products have shipped to real customers. Yours clips onto the bottle you already own, counts every sip, and locks the apps you choose until you catch up.
$59.99 + shipping & tax · Cancel any time before it ships · 30 days to change your mind once it arrives, and we pay return shipping
How it compares
Four ways to drink more water
Three of these already exist in your life and haven’t worked. Here’s the honest difference.
| Approach | A reminder app | A smart bottle | A clip-on reminder | Sponge |
|---|---|---|---|---|
| Roughly what it costs | Free | Around $80 and up | Around $30 | $59.99 |
| Keep the bottle you own | Yes | No — it replaces it | Yes | Yes |
| Measures what you actually drink | No — you log it by hand | Yes | No — it only reminds you | Yes, automatically |
| Syncs to Apple Health | Some do | Yes | Nothing to sync | Yes, on iPhone |
| Does something when you fall behind | Sends a notification | Lights up | Blinks | Locks the apps you chose |
| Still in use after a month | Rarely | Depends on you | Depends on you | That’s what Hydration Locks are for |
Prices are what these categories typically sell for, not quotes for any one product. Want the longer version? We wrote up smart bottles vs clip-on trackers.
Before you buy
The honest answers
The things worth knowing before you spend $59.99.
“I’ll stop using it after a month.”
Most people do — that’s the entire problem with hydration tracking, and it’s the reason App Lock exists. A number you can ignore gets ignored. Apps you can’t open until you drink do not.
“Why $59.99 when a reminder clip is $30?”
Because a reminder clip blinks at you. Sponge measures the water, syncs it, and acts on it. If a blinking light is enough for you, genuinely buy the cheaper thing — it works for some people.
“It’s a pre-order with no date.”
True, and we won’t invent one. We build in batches and a batch runs when enough pre-orders are reserved to fill it. Your price is locked, and you can cancel for a full refund any time before it ships.
“Does it work with my bottle?”
It attaches magnetically to the base, so insulated steel, plastic and glass all work. The adhesive 3-pack lets you leave a mount on every bottle you use and move one tracker between them.