# Interval Flow vs sakun

The clearest difference is monetization model: sakun at free with in-app purchases against Interval Flow's subscription. sakun also leads on review sentiment (58% vs 48%) and iOS requirement (14.0 vs 18.6). On price, rating, ratings volume and update cadence there is nothing between them.

Both are free to download. Interval Flow sells 10 in-app purchases, starting at $4.99 per 3 months and sakun sells 9 in-app purchases, starting at $4.99 per 7 days. Whichever you choose, the download price is not the number that matters.

Interval Flow holds the better App Store score, 4.7 against 4.5. Both are backed by a comparable volume of ratings — 167 and 137 respectively. Written reviews complicate that: 48% of Interval Flow's written reviews are positive against 58% of sakun's, so the app with the better star average is not the one people write more warmly about.

Interval Flow ships an update fortnightly, sakun every 3 weeks. The most recent releases landed on October 23, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | Interval Flow | sakun |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.7 (167 ratings)](https://appshunter.io/ios/app/interval-flow-wod-timer/id6444124987/reviews)** | [4.5 (137 ratings)](https://appshunter.io/ios/app/sakundeep-sleep-relaxation/id6450653536/reviews) |
| Number of ratings | **167** | 137 |
| Positive reviews | 48.1% of reviews | **58.3% of reviews** |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | **Fortnightly** | Every 3 weeks |
| Monetization | Subscription | **Free with in-app purchases** |
| Size | 20 MB | 173 MB |
| Requires iOS | 18.6 | **14.0** |
| Devices | iPhone, iPad | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [Bence Kaposzta](https://appshunter.io/developer/1650069302) | [SAKUN LLC](https://appshunter.io/developer/1694233904) |

## What reviewers say

### Interval Flow

[App page](https://appshunter.io/ios/app/interval-flow-wod-timer/id6444124987)

This app revolutionizes fitness routines with deep customization and advanced tracking for various activities like HIIT, Yoga, and CrossFit. It allows users to create, share, and follow personalized workouts with features like color-coded intervals, real-time progress tracking, and voice assistance.

**Highlights:** Color-coded intervals, Customizable circuits, Real-time progress tracking, Voice assist and search, Exercise library, Workout sharing

**Features:** macOS Compatibility

**In-app purchases (10)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 3 Month | $4.99 | per 3 months |
| 1 Month | $9.99 | per month |
| 1 Month, 3 day trial | $9.99 | per month |
| Annual | $14.99 | per year |
| 1 Year discounted | $25.95 | per year |
| 1 Year, 3 day trial | $39.99 | per year |
| 1 Year | $39.99 | per year |
| 1 Year Intro month | $39.99 | per year |
| Free Lifetime subscription | Free | one-time |
| Lifetime | $24.99 | one-time |

**What reviewers like**

- 👍 Nicely designed with good features
- 👍 Unique and brilliantly for keeping fit
- 👍 Simplicity gets it done

**What reviewers complain about**

- 🐛 App crashes on launch
- 🐛 App doesn't remember interval settings
- 🐛 App rearranges workout order
- 🐛 Cannot see questionnaire properly
- 🐛 Robot voice with no visual instructions

**Reported bugs**

- Programs deleted after update
- App crashes when adding a program
- Show/Hide Instructions adds time to interval
- App defaults to unused workout
- Cannot permanently skip to end of timed activity

**Requested features**

- Increase repetitions to 20
- Streamline adding intervals
- Make it possible to hide unused workouts
- Add music integration or option
- Provide visual instructions for moves


### sakun

[App page](https://appshunter.io/ios/app/sakundeep-sleep-relaxation/id6450653536)

This app offers a sanctuary for deep sleep with soothing white noise, peaceful bedtime stories, and guided meditations. Create personalized soundscapes to block distractions and unwind your mind for restorative rest.

**Highlights:** Customizable sleep soundscapes, Relaxing bedtime stories, Guided meditation exercises, Smart sleep timer, ASMR and nature sounds

**In-app purchases (9)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Sakun Premium: Weekly Plan | $4.99 | per 7 days |
| Sakun Pro: 1 Month Plan | $9.99 | per month |
| Sakun Pro:3 Months Membership | $19.99 | per 3 months |
| Sakun Pro: 1 Year Membership | $29.99 | per year |
| Sakun Pro: 1 Year Membership | $39.99 | per year |
| Sakun Pro: 1 Year Membership | $49.99 | per year |
| Sakun Pro: 1 Year Membership | $119.99 | per year |
| Sakun plus:New Content | $4.99 | one-time |
| Sakun: Lifetime Subscription | $149.99 | one-time |


## Frequently asked questions

### Is Interval Flow free?

Interval Flow is free to download, with in-app purchases available.

### Is sakun free?

sakun is free to download, with in-app purchases available.

### Which has better reviews, Interval Flow or sakun?

Interval Flow is rated higher. Interval Flow averages 4.7 out of 5 from 167 ratings, while sakun averages 4.5 from 137 ratings.

### Do Interval Flow or sakun have ads?

Neither Interval Flow nor sakun shows ads.

### Which is updated more often, Interval Flow or sakun?

Interval Flow ships an update fortnightly, and sakun every 3 weeks. Most recently, Interval Flow was updated on October 23, 2026 and sakun on October 24, 2026.

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*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*