# HIIT Timer vs Flippi Custom Insoles

The clearest difference is price: Flippi Custom Insoles at Free against HIIT Timer's $0.99. Flippi Custom Insoles also leads on update cadence (every 10 days vs every 2 months) and iOS requirement (14.6 vs 17.5). On ads, in-app purchases and device support there is nothing between them.

Flippi Custom Insoles is free to download; HIIT Timer costs $0.99 up front. Neither carries in-app purchases, so what you see is what you pay.

HIIT Timer ships an update every 2 months, Flippi Custom Insoles every 10 days. The most recent releases landed on October 9, 2026 and October 10, 2026 respectively.

## The numbers

| Metric | HIIT Timer | Flippi Custom Insoles |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 2 months | **Every 10 days** |
| Size | 2 MB | 207 MB |
| Requires iOS | 17.5 | **14.6** |
| Devices | iPhone, iPad | iPhone, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Peter Lebedev](https://appshunter.io/developer/1760407520) | [ReTiSense](https://appshunter.io/developer/975451986) |

## What reviewers say

### HIIT Timer

[App page](https://appshunter.io/ios/app/hiit-timer-interval-flex/id6596603930)

**Features:** macOS Compatibility

**In-app purchases:** none


### Flippi Custom Insoles

[App page](https://appshunter.io/ios/app/flippi-custom-insoles/id6737497051)

**In-app purchases:** none


## Frequently asked questions

### Is HIIT Timer free?

HIIT Timer costs $0.99, with no in-app purchases.

### Is Flippi Custom Insoles free?

Flippi Custom Insoles is free to download, with no in-app purchases.

### Do HIIT Timer or Flippi Custom Insoles have ads?

Neither HIIT Timer nor Flippi Custom Insoles shows ads.

### Which is updated more often, HIIT Timer or Flippi Custom Insoles?

HIIT Timer ships an update every 2 months, and Flippi Custom Insoles every 10 days. Most recently, HIIT Timer was updated on October 9, 2026 and Flippi Custom Insoles on October 10, 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.*