# Keyboard² vs HRM Hub

The clearest difference is update cadence: HRM Hub at every 2 months against Keyboard²'s every 12 months. Keyboard²'s advantage is iOS requirement (13.0 vs 15.1). On price, ads, in-app purchases and device support there is nothing between them.

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

Keyboard² ships an update every 12 months, HRM Hub every 2 months. The most recent releases landed on September 13, 2026 and September 14, 2026 respectively.

## The numbers

| Metric | Keyboard² | HRM Hub |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.0 (1 ratings)](https://appshunter.io/ios/app/keyboard/id1337674728/reviews)** | — |
| Number of ratings | **1** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 12 months | **Every 2 months** |
| Monetization | Free | — |
| Size | 11 MB | 56 MB |
| Requires iOS | **13.0** | 15.1 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 17+ |
| Developer | [Takuto Nakamura](https://appshunter.io/developer/1203150472) | [Linn IT Solution Co.,Ltd.](https://appshunter.io/developer/1564423593) |

## What reviewers say

### Keyboard²

[App page](https://appshunter.io/ios/app/keyboard/id1337674728)

This custom keyboard app allows you to play musical notes and chords directly from your device's keyboard. It supports entering numbers, mathematical symbols, and ABC music notation, with the ability to play sounds and chords.

**Highlights:** Play musical notes and chords, Enter numbers and mathematical symbols, Supports ABC music notation, Play sounds, Custom keyboard functionality

**Features:** Vision Pro support

**In-app purchases:** none


### HRM Hub

[App page](https://appshunter.io/ios/app/hrm-hub/id6502644056)

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

**In-app purchases:** none


## Frequently asked questions

### Is Keyboard² free?

Keyboard² is free to download, with no in-app purchases.

### Is HRM Hub free?

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

### Do Keyboard² or HRM Hub have ads?

Neither Keyboard² nor HRM Hub shows ads.

### Which is updated more often, Keyboard² or HRM Hub?

Keyboard² ships an update every 12 months, and HRM Hub every 2 months. Most recently, Keyboard² was updated on September 13, 2026 and HRM Hub on September 14, 2026.

---

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