# HIIT Timer vs VO2 Max Trainer

The clearest difference is price: VO2 Max Trainer at Free against HIIT Timer's $0.99. VO2 Max Trainer also leads on update cadence (weekly vs every 2 months). HIIT Timer's advantage is in-app purchases (none vs 7). On ads, device support and iOS requirement there is nothing between them.

VO2 Max Trainer is free to download; HIIT Timer costs $0.99 up front. VO2 Max Trainer sells 7 in-app purchases, starting at $1.99 per 7 days. HIIT Timer asks for nothing beyond the download.

HIIT Timer ships an update every 2 months, VO2 Max Trainer weekly. The most recent releases landed on October 9, 2026 and October 15, 2026 respectively.

## The numbers

| Metric | HIIT Timer | VO2 Max Trainer |
| --- | --- | --- |
| Price | $0.99 | **Free** |
| Rating | — | **[4.0 (4 ratings)](https://appshunter.io/ios/app/vo2-max-trainer-hiit-zone-2/id6736629740/reviews)** |
| Number of ratings | — | **4** |
| Positive reviews | — | 0.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 2 months | **Weekly** |
| Monetization | — | Free with in-app purchases |
| Size | 2 MB | 286 MB |
| Requires iOS | **17.5** | 18.6 |
| Devices | iPhone, iPad | **iPhone, iPad, Apple Watch** |
| Age rating | 4+ | 4+ |
| Developer | [Peter Lebedev](https://appshunter.io/developer/1760407520) | [Kevin Floch](https://appshunter.io/developer/1772752224) |

## What reviewers say

### HIIT Timer

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

**Features:** macOS Compatibility

**In-app purchases:** none


### VO2 Max Trainer

[App page](https://appshunter.io/ios/app/vo2-max-trainer-hiit-zone-2/id6736629740)

Measure, track, and improve your VO2 Max with a variety of fitness tests and personalized training plans. Features include HIIT and Zone 2 workouts, progress tracking, and integration with Apple Watch and HealthKit.

**Highlights:** Measure VO2 Max with 5 fitness tests, HIIT and Zone 2 training, Track progress and compare to leaderboards, Apple Watch integration, HealthKit integration, Training readiness scoring, Fitness age calculation

**Features:** macOS Compatibility, Apple Watch app, Vision Pro support

**In-app purchases (7)**

| Purchase | Price | Billing |
| --- | --- | --- |
| VO2_Weekly | $1.99 | per 7 days |
| VO2_Monthly | $1.99 | per month |
| VO2_Annually | $14.99 | per year |
| VO2_Lifetime_Upgrade | $9.99 | one-time |
| VO2_Lifetime_Upgrade2 | $14.99 | one-time |
| VO2_Lifetime | $19.99 | one-time |
| VO2_Lifetime2 | $29.99 | one-time |


## Frequently asked questions

### Is HIIT Timer free?

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

### Is VO2 Max Trainer free?

VO2 Max Trainer is free to download, with in-app purchases available.

### Do HIIT Timer or VO2 Max Trainer have ads?

Neither HIIT Timer nor VO2 Max Trainer shows ads.

### Which is updated more often, HIIT Timer or VO2 Max Trainer?

HIIT Timer ships an update every 2 months, and VO2 Max Trainer weekly. Most recently, HIIT Timer was updated on October 9, 2026 and VO2 Max Trainer on October 15, 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.*