# Protocol vs Espir

The clearest difference is in-app purchases: Protocol at none against Espir's 2. Espir's advantage is update cadence (every 3 weeks vs every 2 months) and iOS requirement (15.0.0 vs 18.0). On price, ads and device support there is nothing between them.

Both are free to download. Espir sells 2 in-app purchases, starting at $9.99 per month. Protocol asks for nothing beyond the download.

Protocol ships an update every 2 months, Espir every 3 weeks. The most recent releases landed on October 30, 2026 and October 31, 2026 respectively.

## The numbers

| Metric | Protocol | Espir |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (4 ratings)](https://appshunter.io/ios/app/protocol-sound-system/id6745834104/reviews)** | — |
| Number of ratings | **4** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 2 months | **Every 3 weeks** |
| Monetization | Paid | — |
| Size | 1 MB | 46 MB |
| Requires iOS | 18.0 | **15.0.0** |
| Devices | iPhone | **iPhone, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [hsla0001](https://appshunter.io/developer/1778537322) | [Louis Collin](https://appshunter.io/developer/1881203914) |

## What reviewers say

### Protocol

[App page](https://appshunter.io/ios/app/protocol-sound-system/id6745834104)

This app generates refined ambient noise with a unique tactile and visual experience. It offers precise control over sound frequencies and features an elegant particle system that responds to touch, designed for focus, calm, and sleep.

**Highlights:** Ambient noise generation, Touch-responsive particle system, Precise frequency control, Haptic feedback, Background playback, Media controls integration

**In-app purchases:** none


### Espir

[App page](https://appshunter.io/ios/app/espir-mindful-eating/id6759850459)

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Espir Monthly | $9.99 | per month |
| Espir Annual | $29.99 | per year |


## Frequently asked questions

### Is Protocol free?

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

### Is Espir free?

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

### Do Protocol or Espir have ads?

Neither Protocol nor Espir shows ads.

### Which is updated more often, Protocol or Espir?

Protocol ships an update every 2 months, and Espir every 3 weeks. Most recently, Protocol was updated on October 30, 2026 and Espir on October 31, 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.*