# sleep vs Open Bridge

The clearest difference is review sentiment: sleep at 73% against Open Bridge's 0%. sleep also leads on device support (3 vs 1) and iOS requirement (9.0 vs 16.4). Open Bridge's advantage is in-app purchases (none vs 3) and update cadence (every 5 weeks vs every 8 months). On price and ads there is nothing between them.

Both are free to download. sleep sells 3 in-app purchases, starting at $2.99 per month. Open Bridge asks for nothing beyond the download.

sleep ships an update every 8 months, Open Bridge every 5 weeks. The most recent releases landed on October 23, 2026 and October 6, 2026 respectively.

## The numbers

| Metric | sleep | Open Bridge |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (5 ratings)](https://appshunter.io/ios/app/open-bridge/id1578358408/reviews)** |
| Number of ratings | — | **5** |
| Positive reviews | **72.7% of reviews** | 0.0% of reviews |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 8 months | **Every 5 weeks** |
| Monetization | Freemium | **Free** |
| Size | 27 MB | 41 MB |
| Requires iOS | **9.0** | 16.4 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Neuro Summum Inc.](https://appshunter.io/developer/1447290703) | [Sage Bionetworks, a Not-For-Profit Research Organization](https://appshunter.io/developer/972180603) |

## What reviewers say

### sleep

[App page](https://appshunter.io/ios/app/sleep-2-peak-sleep-need-tool/id557632863)

This tool helps you understand your body's natural sleep needs and circadian rhythm. Measure alertness variations with simple tests to optimize your daily schedule for peak performance and wellbeing. Export your data for personal use or research.

**Highlights:** Measure alertness variations, Identify unique circadian rhythm, Optimize sleep and activity schedules, Scientifically validated reaction time test, Track texting speed variations, Exportable user data

**Features:** macOS Compatibility

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| sleep-2-Peak Premium | $2.99 | per month |
| sleep-2-Peak Premium Monthly | $2.99 | per month |
| sleep-2-Peak Premium Yearly | $19.99 | per year |


### Open Bridge

[App page](https://appshunter.io/ios/app/open-bridge/id1578358408)

Contribute your data to scientific research studies focused on cognition. Complete scheduled activities, similar to puzzles or memory tests, directly on your phone. Your identity is protected as the app collects data solely for research purposes.

**Highlights:** Contribute data for research studies, Complete scheduled cognitive activities, Activities resemble puzzles and memory tests, Data used solely for research, Protects user identity, Developed by non-profit research organizations

**In-app purchases:** none


## Frequently asked questions

### Is sleep free?

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

### Is Open Bridge free?

Open Bridge is free to download, with no in-app purchases.

### Do sleep or Open Bridge have ads?

Neither sleep nor Open Bridge shows ads.

### Which is updated more often, sleep or Open Bridge?

sleep ships an update every 8 months, and Open Bridge every 5 weeks. Most recently, sleep was updated on October 23, 2026 and Open Bridge on October 6, 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.*