# Seconds Interval Timer vs VO2 Flow

The clearest difference is ads: Seconds Interval Timer at none against VO2 Flow's shown. VO2 Flow's advantage is iOS requirement (13.0 vs 18.0). On price, update cadence, in-app purchases and device support there is nothing between them.

Both are free to download. Seconds Interval Timer sells 1 one-off in-app purchase and VO2 Flow sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

Seconds Interval Timer ships an update monthly, VO2 Flow every 5 weeks. The most recent releases landed on October 18, 2026 and September 25, 2026 respectively.

## The numbers

| Metric | Seconds Interval Timer | VO2 Flow |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.7 (24K ratings)](https://appshunter.io/ios/app/seconds-interval-timer/id475816966/reviews)** | — |
| Number of ratings | **24K** | — |
| In-app purchases | Yes | Yes |
| Ads | **No** | Yes |
| Update frequency | **Monthly** | Every 5 weeks |
| Monetization | Free with in-app purchases | — |
| Size | 95 MB | 25 MB |
| Requires iOS | 18.0 | **13.0** |
| Devices | iPhone, iPad, Apple Watch | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Runloop Ltd](https://appshunter.io/developer/325563420) | [CHRISTOPHER DISCOTTO](https://appshunter.io/developer/1864553330) |

## What reviewers say

### Seconds Interval Timer

[App page](https://appshunter.io/ios/app/seconds-interval-timer/id475816966)

This app provides a versatile interval timer for various workout types like Tabata, HIIT, and circuit training. It features a clear, full-screen display, customizable alerts, and background operation. Users can also utilize a stopwatch and countdown timer, with integration for Apple Health.

**Highlights:** Full-screen colored display, Templates for HIIT, Tabata, Circuit Training, Voice and audio alerts, Music assignment per interval, Background operation, Apple Health integration, Stopwatch and countdown timer

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Advanced Version | $7.99 | one-time |

**What reviewers like**

- 🚀 Great workout app
- 👍 Customizable and user-friendly
- 🔒 Reliable and stable
- 💡 Versatile for various workouts
- 👍 Easy to create and edit timers

**What reviewers complain about**

- 🐛 Occasional audio issues
- 🔍 Limited Apple Watch integration
- 💰 Paid version required for full functionality
- 🕰️ Time-consuming to set up complex workouts

**Reported bugs**

- Timer sometimes stops working unexpectedly
- Issues with restoring purchases on new devices

**Requested features**

- Ability to change beep/alert volume independently
- Option to delay transition between intervals
- Sync workouts across devices
- More preset workout templates
- Heart rate monitoring integration


### VO2 Flow

[App page](https://appshunter.io/ios/app/vo2-flow-norwegian-4x4-timer/id6757104585)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pro Upgrade | $4.99 | one-time |


## Frequently asked questions

### Is Seconds Interval Timer free?

Seconds Interval Timer is free to download, with in-app purchases available.

### Is VO2 Flow free?

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

### Do Seconds Interval Timer or VO2 Flow have ads?

VO2 Flow shows ads; Seconds Interval Timer does not.

### Which is updated more often, Seconds Interval Timer or VO2 Flow?

Seconds Interval Timer ships an update monthly, and VO2 Flow every 5 weeks. Most recently, Seconds Interval Timer was updated on October 18, 2026 and VO2 Flow on September 25, 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.*