# HPI vs Frequency

The clearest difference is in-app purchases: HPI at none against Frequency's 10. Frequency's advantage is update cadence (every 10 days vs every 2 months). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. Frequency sells 9 in-app purchases, starting at $7.99 per 7 days. HPI asks for nothing beyond the download.

HPI ships an update every 2 months, Frequency every 10 days. The most recent releases landed on October 29, 2026 and November 3, 2026 respectively.

## The numbers

| Metric | HPI | Frequency |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[3.9 (24 ratings)](https://appshunter.io/ios/app/frequency-hz-tone-generator/id1671426872/reviews)** |
| Number of ratings | — | **24** |
| Positive reviews | — | 0.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 2 months | **Every 10 days** |
| Monetization | — | Free with in-app purchases |
| Size | 46 MB | 16 MB |
| Requires iOS | **15.6** | 16.0 |
| Devices | iPhone, iPod | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Idwell GmbH](https://appshunter.io/developer/1269662593) | [Optimize IT](https://appshunter.io/developer/1671426874) |

## What reviewers say

### HPI

[App page](https://appshunter.io/ios/app/hpi/id1491749568)

**In-app purchases:** none


### Frequency

[App page](https://appshunter.io/ios/app/frequency-hz-tone-generator/id1671426872)

Generate precise audio frequencies for various purposes, from tuning instruments to cleaning water from speakers. Explore different waveforms and customize sound generation for unique audio experiences. Elevate your audio quality and functionality.

**Highlights:** Generate frequencies from 1 Hz to 40,000 Hz, Clean water/moisture from speakers, Produce sine, triangle, sawtooth, and square waveforms, Tune musical instruments, Select notes and octaves for specific pitches, Play multiple frequencies simultaneously

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

**In-app purchases (9)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Weekly Premium | $7.99 | per 7 days |
| Weekly | $9.99 | per 7 days |
| Weekly VIP | $9.99 | per 7 days |
| Monthly Premium | $17.99 | per month |
| Monthly | $19.99 | per month |
| Annual VIP | $24.99 | per year |
| Annual Premium | $24.99 | per year |
| Annual VIP | $29.99 | per year |
| Annual | $29.99 | per year |


## Frequently asked questions

### Is HPI free?

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

### Is Frequency free?

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

### Do HPI or Frequency have ads?

Neither HPI nor Frequency shows ads.

### Which is updated more often, HPI or Frequency?

HPI ships an update every 2 months, and Frequency every 10 days. Most recently, HPI was updated on October 29, 2026 and Frequency on November 3, 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.*