# IntervalTimer vs Muscle Stamp

The clearest difference is in-app purchases: Muscle Stamp at none against IntervalTimer's 1. IntervalTimer's advantage is device support (3 vs 1) and iOS requirement (15.1 vs 17.0). On price, update cadence and ads there is nothing between them.

Both are free to download. IntervalTimer sells 1 one-off in-app purchase. Muscle Stamp asks for nothing beyond the download.

IntervalTimer ships an update weekly, Muscle Stamp every 4 days. The most recent releases landed on October 25, 2026 and October 14, 2026 respectively.

## The numbers

| Metric | IntervalTimer | Muscle Stamp |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (1 ratings)](https://appshunter.io/ios/app/muscle-stamp/id6780130811/reviews)** |
| Number of ratings | — | **1** |
| Positive reviews | — | 100.0% of reviews |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Weekly | **Every 4 days** |
| Monetization | — | Free |
| Size | 52 MB | 42 MB |
| Requires iOS | **15.1** | 17.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [naoki otsu](https://appshunter.io/developer/1082476153) | [Kazuki Ohya](https://appshunter.io/developer/6780130813) |

## What reviewers say

### IntervalTimer

[App page](https://appshunter.io/ios/app/intervaltimer-workout-timer/id6761044639)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium (Pay Once) | $4.99 | one-time |


### Muscle Stamp

[App page](https://appshunter.io/ios/app/muscle-stamp/id6780130811)

Effortlessly log your workouts with a single tap for each muscle group trained. Set personalized weekly goals, track your training streaks, and visualize your progress over time. Focus on your fitness without the hassle of complex tracking.

**Highlights:** One-tap muscle group logging, Personalized weekly training goals, Workout streak tracking, Progress visualization, Built-in session timer

**In-app purchases:** none


## Frequently asked questions

### Is IntervalTimer free?

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

### Is Muscle Stamp free?

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

### Do IntervalTimer or Muscle Stamp have ads?

Neither IntervalTimer nor Muscle Stamp shows ads.

### Which is updated more often, IntervalTimer or Muscle Stamp?

IntervalTimer ships an update weekly, and Muscle Stamp every 4 days. Most recently, IntervalTimer was updated on October 25, 2026 and Muscle Stamp on October 14, 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.*