# AB BMI Plus vs Protocol

The clearest difference is iOS requirement: AB BMI Plus at 16.5 against Protocol's 18.0. On price, update cadence, ads and in-app purchases there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

AB BMI Plus ships an update every 3 months, Protocol every 2 months. The most recent releases landed on October 17, 2026 and September 28, 2026 respectively.

## The numbers

| Metric | AB BMI Plus | Protocol |
| --- | --- | --- |
| 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 | No |
| Ads | No | No |
| Update frequency | Every 3 months | **Every 2 months** |
| Monetization | — | Paid |
| Size | 9 MB | 1 MB |
| Requires iOS | **16.5** | 18.0 |
| Devices | **iPhone, iPad** | iPhone |
| Age rating | +4 | 4+ |
| Developer | [Alexander Berkovich](https://appshunter.io/developer/1460157188) | [hsla0001](https://appshunter.io/developer/1778537322) |

## What reviewers say

### AB BMI Plus

[App page](https://appshunter.io/ios/app/ab-bmi-plus/id1622389050)

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

**In-app purchases:** none


### 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


## Frequently asked questions

### Is AB BMI Plus free?

AB BMI Plus is free to download, with no in-app purchases.

### Is Protocol free?

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

### Do AB BMI Plus or Protocol have ads?

Neither AB BMI Plus nor Protocol shows ads.

### Which is updated more often, AB BMI Plus or Protocol?

AB BMI Plus ships an update every 3 months, and Protocol every 2 months. Most recently, AB BMI Plus was updated on October 17, 2026 and Protocol on September 28, 2026.

---

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