# Sumi: Deep Work Focus — Take a break from you phone

> Productivity app to reduce phone usage with timed breaks and alerts. (iPhone/iPad app by David Park.)

- Source: https://appshunter.io/ios/app/sumi-deep-work-focus/id6448810281 (this page in markdown: same URL + `.md`)
- Developer: [David Park](https://appshunter.io/developer/1686485618)
- Category: Productivity, Lifestyle
- Price: Free with in-app purchases
- Rating: 3.00/5 from 2 App Store ratings · 2 written reviews indexed
- Age rating: 4+
- Requires: iOS 16.0 · 10 MB
- Languages: English
- Released: 2023-05-05
- Data updated: 2026-08-11
- Monetization: free
- User reviews in markdown: https://appshunter.io/ios/app/sumi-deep-work-focus/id6448810281/reviews.md

## What is Sumi?

The most beautiful thing an app can do is get out of your way.

Sumi sits quietly on cream paper, holds your attention for an hour, and asks for nothing back. Set a length. Put your phone face down. Pick it up before the time is done and the session breaks — not as a punishment, but as a commitment kept.

No ads. No notifications. No streaks-as-slot-machines. No weekly subscription trap. Just deep work, and the quiet record of the hours you've given it.

— THE RITUAL —
Set an intention and a length. Put the phone down. Sumi keeps watch: lift it, or leave the app, and the session ends. When the time is held, the line completes, your lifetime hours grow, and the session is logged. Silent while you work. Quietly rewarding when you finish.

— A CALM LEDGER, NOT A GAME —
The number that only goes up: your lifetime hours focused. A streak, if you want one. A week that fills, a line that climbs. No characters to feed, no points, no dark patterns. Progress you can feel, with nothing engineered to hook you.

— MADE FOR DEEP-WORK PEOPLE —
For writers, developers, designers, students of a craft — anyone who already romanticizes focus and resents apps built to fracture it. Graphite and cream. Monospace. Paper grain. A single calligraphic mark.

— PAY ONCE —
Your focus shouldn't be a recurring charge. Sumi is free to use, with an optional one-time Lifetime unlock (or a subscription, if you prefer) for custom lengths, full history and trends, themes, and session intentions.

Put the phone down. Pick the work up.

———
Privacy Policy: https://dayonefoundry.com/sumi/privacy
Terms of Use (EULA): https://dayonefoundry.com/sumi/terms

## Key features

- Timed phone breaks
- Movement alerts
- Productivity enhancement
- Mental health improvement
- Simple interface

## Pricing and in-app purchases

Base price: Free.

**Subscriptions**

| Subscription | Price | Period |
| --- | --- | --- |
| Sumi Pro Monthly | $5.99 | per month |
| Sumi Pro Annual | $24.99 | per year |

**One-time purchases**

| Purchase | Price | Type |
| --- | --- | --- |
| Sumi Pro Lifetime | $49.99 | one-time |


## Recent user reviews (2 of 2)

All indexed reviews: https://appshunter.io/ios/app/sumi-deep-work-focus/id6448810281/reviews.md

### 3/5 — Doesn’t work

*2026-04-01*

Once your phone turns off from not using it or touching it then the timer stops

### 3/5 — Doesn’t work

*2025-06-16*

I like the concept a lot, but the moment you start a timer it ends because your phone is open…

**Developer response:** Hey! You have to put your phone flat on your table and press start. The app is designed so you can't touch our move your phone or it interrupts the timer.

## Frequently asked questions about Sumi

### Does No Phone Mode have ads?

No Phone Mode does not contain advertisements.

### What is the user rating for No Phone Mode?

No Phone Mode has a rating of 3.0 stars based on 1 review.

### How often is No Phone Mode updated?

The latest version, 0.0.3, was released on June 26, 2023. The app was first released on May 5, 2023.

### What devices is No Phone Mode available on?

No Phone Mode is available for iPhone and iPod devices.

### What is the age rating for No Phone Mode?

No Phone Mode has an age rating of 4+.

### How does No Phone Mode help with productivity?

By encouraging timed breaks and alerting users if they interact with their phone, No Phone Mode aims to minimize distractions and improve focus on other tasks.

### Can No Phone Mode be used offline?

The description does not specify offline functionality, but the core features of setting timers and triggering alerts suggest it may require an active connection for full operation.

## Version history (last 5 releases)

### 1.0.3 — 2026-06-27

Small wording refinements and a calmer finish to each session.

### 1.0.1 — 2026-06-21

Polish and small improvements.

### 0.0.3 — 2023-06-26

New Design for significantly improved battery drain.

### 0.0.2 — 2023-05-07

Bug fix

### 0.0.1 — 2023-05-05

No release notes.

## Apps similar to Sumi

| App | Rating | Price | Category |
| --- | --- | --- | --- |
| [Mornings: Morning Screen Time](https://appshunter.io/ios/app/mornings-morning-screen-time/id6458836460) | 4.7 (7) | Free | Productivity |
| [Simple Phone: Minimalist](https://appshunter.io/ios/app/simple-phone-minimalist/id6670218965) | 4.2 (41) | Free | Productivity |
| [Flip Timer: offscreen focus](https://appshunter.io/ios/app/flip-timer-offscreen-focus/id1543547997) | 5.0 (1) | Free | Productivity |
| [Superhappy Screen Time Blocker](https://appshunter.io/ios/app/superhappy-screen-time-blocker/id6479611902) | 4.6 (280) | Free | Productivity |
| [BB - Screen Time & App Blocker](https://appshunter.io/ios/app/bb-screen-time-and-app-blocker/id6443657745) | 4.9 (391) | Free | Productivity |
| [DEApp -](https://appshunter.io/ios/app/deapp/id6459658940) | 5.0 (4) | Free | Productivity |

## More apps by David Park

- [Camera Remote: Photos Together](https://appshunter.io/ios/app/camera-remote-photos-together/id6448898384)
- [How We Feeling?](https://appshunter.io/ios/app/how-we-feeling/id6451378431)
- [Did You Gym? Gym Streak](https://appshunter.io/ios/app/did-you-gym-gym-streak/id6458977236)
- [Pregnancy Daily Progress](https://appshunter.io/ios/app/pregnancy-daily-progress/id6466779170)
- [Photo Coach AI - 4 Dating Apps](https://appshunter.io/ios/app/photo-coach-ai-4-dating-apps/id6670407821)

All apps by David Park: https://appshunter.io/developer/1686485618

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-11.*