# REM Sleep Tracker vs I Ching

The clearest difference is update cadence: I Ching at daily against REM Sleep Tracker's every 2 weeks. REM Sleep Tracker's advantage is iOS requirement (16.0 vs 18.6). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. REM Sleep Tracker sells 2 in-app purchases, starting at $9.99 per year and I Ching sells 5 one-off in-app purchases. Whichever you choose, the download price is not the number that matters.

REM Sleep Tracker ships an update every 2 weeks, I Ching daily. The most recent releases landed on November 3, 2026 and November 9, 2026 respectively.

## The numbers

| Metric | REM Sleep Tracker | I Ching |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.2 (49 ratings)](https://appshunter.io/ios/app/rem-sleep-tracker/id6446677275/reviews)** | — |
| Number of ratings | **49** | — |
| Positive reviews | 0.0% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | Every 2 weeks | **Daily** |
| Monetization | Freemium | — |
| Size | 25 MB | 196 MB |
| Requires iOS | **16.0** | 18.6 |
| Devices | iPhone | **iPhone, iPad** |
| Age rating | 4+ | 4+ |
| Developer | [Nicola Eusebi](https://appshunter.io/developer/737311863) | [Giulio Ginesi](https://appshunter.io/developer/1883512745) |

## What reviewers say

### REM Sleep Tracker

[App page](https://appshunter.io/ios/app/rem-sleep-tracker/id6446677275)

This app analyzes Apple Watch sensor data to provide a sleep quality score. It offers detailed insights into sleep stages, heart rate, and weekly trends, helping users understand and improve their rest habits.

**Highlights:** Sleep quality scoring, Detailed sleep stage analysis (light, deep, REM), Heart rate monitoring, Weekly trend tracking, Sleep bank concept for habit analysis, Apple Health integration

**Features:** macOS Compatibility, Vision Pro support

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Sleep Score Premium Yearly | $9.99 | per year |
| Sleep Score Premium Yearly | $29.99 | per year |


### I Ching

[App page](https://appshunter.io/ios/app/i-ching-psyche/id6760262424)

**Features:** macOS Compatibility, Family Sharing, Vision Pro support

**In-app purchases (5)**

| Purchase | Price | Billing |
| --- | --- | --- |
| One Credit | $0.99 | one-time |
| Five Coins | $0.99 | one-time |
| Ten Coins | $1.99 | one-time |
| Thirty Coins | $2.99 | one-time |
| Unlimited Castings | $4.99 | one-time |


## Frequently asked questions

### Is REM Sleep Tracker free?

REM Sleep Tracker is free to download, with in-app purchases available.

### Is I Ching free?

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

### Do REM Sleep Tracker or I Ching have ads?

Neither REM Sleep Tracker nor I Ching shows ads.

### Which is updated more often, REM Sleep Tracker or I Ching?

REM Sleep Tracker ships an update every 2 weeks, and I Ching daily. Most recently, REM Sleep Tracker was updated on November 3, 2026 and I Ching on November 9, 2026.

---

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