Datum

The tracker that doesn't track you.

Track anything: a number, a yes-or-no, a mood, a moment. Log it in seconds, or let it log itself.

Download on the App Store iPhone & iPad

Free for up to 10 trackers. Unlimited is a single purchase, nothing renews.

What can you track?

Anything you can put a value on.

6 field types and 84 built-in units across 20 kinds of measurement, plus any currency, percentage, or unit you name.

Finn's weight

just now

15 lb

Vitamins

8m ago

Yes

Mood

1h ago

Good 4

Journal

2h ago

slept great

Date planted

Yesterday

Apr 2

Paint color

3d ago

#FFB224

Log However You Like

The right control for every tracker.

A stepper, a dial, a spinner, a tap or tally pad, or a stopwatch, fit to what you're logging.

Stepper

12

Nudge up or down, one tap at a time.

Dial

0

Sweep around to dial a value in.

Spinner

Flick a wheel to the number.

Tap Pad

Tap once to add one, great for counts.

Tally Pad

2

Rack up tallies in fives.

Stopwatch

0:20

Time it live, hands-free.

Deeply Integrated

Log without opening the app.

Datum reaches into the places you already are, no launch required.

Siri

Say “Log to Weight in Datum,” then the number, hands-free.

Share Sheet

Send a photo or link straight into an entry.

Home Screen

Long-press the icon for a quick action.

Spotlight

Find and open any tracker from search.

Live Activities

A running stopwatch on the Lock Screen and Dynamic Island.

What a check-in looks like

One form, many trackers.

Group the ones that go together, then log them all in one pass instead of one at a time.

It can do the math for you

Calculated fields.

Add one that computes itself from the ones you log, like MPG from miles and gallons or cost per mile from spend and distance, recalculated live on every check-in.

418 mi
12.9 gal
$52.40

MPG

Distance ÷ Fuel

32.4 mpg

Cost per mile

Cost ÷ Distance

$0.13

Cost per gallon

Cost ÷ Fuel

$4.06

Make sense of it

Every value becomes a chart, a streak, a trend.

15+ chart types, an activity heatmap, a map of where you logged it.

Steps

47 entries

8,650

6%

Get a head start

Add a ready-made check-in.

Everything in the Library is free.*

Rise & Shine

Weight, mood, and a good night's sleep — one quick check-in to open the day.

3 slots

Refuel

Odometer, litres, and cost at every fill-up — with fuel economy worked out for you.

3 slots

Hydration & Caffeine

Tap up your glasses of water and cups of coffee as the day goes.

2 slots

Mood & Mind

A mood, a moment of practice, and one thing you're grateful for.

3 slots

Nighty Night

Close out the day — how it went, whether you wound down, and one good thing.

3 slots

Time Tracker

Start the clock, live your life, log it when you stop.

2 slots

6 of the 22 packs in the Library. * 10 slots included for free

Let it happen automatically

Datum can log (or nudge you to log) on its own.

On a schedule, when you arrive somewhere, or whenever another tracker gets a new entry.

Schedule

“Log your weight,” every weekday at 7:00 AM.

Place

Arrive at the gym, and it logs the visit, no tapping.

New Entry

Stock runs low, and Datum nudges you to reorder.

Connected Sources

Some trackers fill themselves in.

Connect Apple Health or Photos on this device, or point a tracker at any web API, and it logs on a schedule with nothing to type.

Resting heart rate

Apple Health

58 bpm

Photos taken

Photos

12 photos

BTC price

Web API

$67,204

Private and Secure, By Design

Yours. Actually yours.

  • No account, no sign-up. Just open the app and start.
  • Works completely offline. No signal, no problem. Everything syncs the moment you're back.
  • Synced privately over your own iCloud. Every device you own. No one else.
  • No analytics, no third parties.* Nothing about you leaves your devices.

* Read the details in the Privacy Policy.

Track anything. Keep it yours.

Download on the App Store iPhone & iPad