That One Thing app icon: an amber numeral one crossed by a coral check markThat One ThingGet it free
iPhone · Watch · Widgets

One task a day.
Finish it.
Repeat.

Every other to-do app helps you collect tasks. That One Thing makes you finish one. Pick the thing that matters, and you can't add another until it's done.

Download free on the App StoreSee how it works
  • Free to use
  • No ads, no tracking
  • iCloud sync
  • 34 languages
7Level 7 · Focused mind+50 XP for finishing
Focus screen of That One Thing on iPhone: today's one thing 'Write the opening chapter' on a coral card with a tap-to-complete circle, a level 6 XP bar and an Up Next list
The problem

Your to-do list isn't broken. Its length is.

Twelve half-finished projects compete for the same attention. So you reorganise the list instead of doing anything on it. Sound familiar?

27

A backlog is a to-don't list

Every unfinished item is a small reminder that you're behind. Twenty-seven of them is a mood, not a plan.

Choosing burns the fuel

Deciding what to do next costs the same attention as doing it. Pick once, in the morning, and stop deciding.

Finishing is the feeling

One completed thing beats six touched ones. The app is built around the moment you tap it done.

How it works

Three taps. One finished thing.

No projects, no tags, no priority matrix. Set it, see it, done.

Set thing screen: a large title field, a note field, background colour swatches and a reminder row
1

Name the one thing

Type it in plain language, add a note to yourself, and set a reminder for the time you'll actually do it.

Focus screen: one coral card holds today's task with a white circle to tap when it's complete
2

Look at it all day

One coral card. Nothing else competing. It's on your home screen widget and your watch too, so it's hard to forget.

Done screen: a running list of finished tasks grouped by day with green check marks and completion times
3

Tap it done

Confetti, a green check, streak +1, XP in the bank. Then it drops into your Done list as permanent proof.

Streaks · XP · 34 badges

A streak you can't lose in one bad day.

Most streak apps punish you for being human. Here, a shield covers the day you missed, so three weeks of showing up doesn't evaporate because of one Tuesday.

12Twelve days in a row.
Two of them were shielded.
TWTFSSM
  • Done.You finished a thing that day.
  • Shielded.A shield covered a missed day.
  • Today.Still open. Go fill it.
7Level 7 · Focused mind340 / 500 XP to level 8

Every completion pays XP. XP becomes levels. Levels unlock a collection of 34 badges, from your very first finish to a full year of showing up.

1102550100365

The whole collection, in one grid.

Awards is the tab you open when you need a reason to keep going. A level ring, an XP bar, and 34 tiles that fill in one at a time, locked ones visible, so you always know what's next.

  • Completion badges
  • Streak badges
  • Level milestones
  • Unlock celebrations
Awards screen: a dark level ring card reading Level 6 Focused, above a three-column grid of 34 badge tiles with unlocked green and coral tiles and locked grey tiles
Stats screen: current streak, best streak and total finished, with a month heatmap of completed days
Receipts

A record of what you actually finished.

Not what you meant to do: what got done, and when. Scroll back to last Tuesday and it's all there, timestamped.

143
All-time
finished
34
Badges to
collect
1
Task at
a time
  • Send the client proposal8:12 AM
  • 30-minute morning walk7:05 AM
Built for ADHD brains

An ADHD task app that doesn't ask you to be organised first.

Most planners assume executive function you're trying to borrow. This one only ever asks a single question: what's the one thing today?

Try it free today
One decision, not twentyChoice paralysis needs choices. Remove them and the task starts itself.
Immediate reward, on purposeXP, confetti, a badge unlock. Dopamine at the moment of finishing, not a week later.
Forgiving by designStreak shields absorb the bad days, so shame never becomes the reason you quit.
In front of you, everywhereHome screen widget, lock screen, Control Center, Apple Watch. Out of sight is out of mind, so it isn't.
Everything else

Small app. Nothing missing.

Widgets & Watch

Home and lock screen widgets, a Control Center control, and a Watch app to tick it off.

Reminders that land

Nudge yourself at the hour you'll actually do it. Multiple reminders per thing.

Make it yours

Accent colours, app icons, custom backgrounds and fonts on your focus card.

34

Languages & access

34 languages, full VoiceOver support, Dynamic Type, dark mode, reduce-motion respected.

Pick your icon

Three finished app icons (chocolate, cream and gradient) so the app looks right on your home screen.

Chocolate app icon variantCream app icon variantGradient app icon variant

Light and dark, properly

Not an inverted screenshot: a second palette, drawn on purpose, in warm espresso.

Focus screen in dark mode on a warm espresso background
Free on the App Store

Download it. Finish something today.

Free to download, and the whole method works without paying a penny. There's an optional Premium upgrade inside the app if you ever want more, nothing to decide right now.

What you get, free
  • One task a day, front and centre
  • Streaks, XP and levels
  • All 34 achievement badges
  • Widget, Watch app and reminders
  • Done log, dark mode, iCloud sync
  • 34 languages, no ads, no tracking
That One Thing app iconGet it free on the App StoreiPhone & Apple Watch
Requires iOS 17 or later
FAQ

Questions people actually ask.

What is a "one thing a day" app?

Instead of holding a long list, it asks you to commit to a single task that matters today. That One Thing keeps it on screen, front and centre, and only lets you add another once it's finished.

Is it good for ADHD?

It's built for it. A single visible task removes the choice paralysis of a twenty-item list, completions give immediate XP feedback, and streak shields mean one bad day doesn't undo weeks of progress.

Is it free?

Yes. One task a day, streaks, XP, all 34 badges, the widget, the Watch app, reminders, dark mode and iCloud sync cost nothing. There's an optional Premium upgrade inside the app for multiple active tasks, streak shields, full stats history and customisation.

What happens if I miss a day?

A streak shield covers it. Miss a day here and there and your streak survives, so three weeks of work isn't wiped out by one hard Tuesday.

Can I ever have more than one task?

Yes, Premium adds multiple active tasks for days when you genuinely need more than one. The free app deliberately holds you to a single focus, because that's the part that works.

Does it work as a habit tracker?

Set the same thing each day and the streak, heatmap and Done log behave exactly like a habit tracker, with one difference: finishing is the only way a day counts.

Is there a widget and a Watch app?

Both. Home and lock screen widgets show today's one thing and your streak at a glance, plus a Control Center control and an Apple Watch app for marking it done from your wrist.

What languages does it support?

34, including German, French, Spanish, Portuguese, Italian, Dutch, Polish, Japanese, Korean, Simplified and Traditional Chinese, Arabic and Hebrew with right-to-left layout.

Where does my data live?

On your device, synced across your own devices with iCloud. No ads, no tracking, no analytics profile of your tasks.

That One Thing app icon

What's your one thing today?

Pick it, finish it, and start a streak worth protecting. Free on the App Store.

Download on the App Store