# Interval Timer Sec+Sec vs コラッツ計算機｜数列シミュレーター

The clearest difference is update cadence: コラッツ計算機｜数列シミュレーター at weekly against Interval Timer Sec+Sec's every 12 months. Interval Timer Sec+Sec's advantage is iOS requirement (13 vs 26.2). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Interval Timer Sec+Sec sells 1 one-off in-app purchase and コラッツ計算機｜数列シミュレーター sells 1 one-off in-app purchase. Whichever you choose, the download price is not the number that matters.

Interval Timer Sec+Sec ships an update every 12 months, コラッツ計算機｜数列シミュレーター weekly. The most recent releases landed on October 29, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | Interval Timer Sec+Sec | コラッツ計算機｜数列シミュレーター |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[3.7 (13 ratings)](https://appshunter.io/ios/app/interval-timer-sec-plus-sec/id595618563/reviews)** | — |
| Number of ratings | **13** | — |
| Positive reviews | 77.8% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | Yes | Yes |
| Update frequency | Every 12 months | **Weekly** |
| Monetization | Ad-supported | — |
| Size | 12 MB | 5 MB |
| Requires iOS | **13** | 26.2 |
| Devices | iPhone, iPod | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [SHIGETO TAKAGI](https://appshunter.io/developer/519611619) | [Kenji Yanase](https://appshunter.io/developer/1865920313) |

## What reviewers say

### Interval Timer Sec+Sec

[App page](https://appshunter.io/ios/app/interval-timer-sec-plus-sec/id595618563)

This free interval training timer app uses alarms and vibrations to mark specified second intervals. It automatically tracks repetitions and remembers your settings, making it ideal for High Intensity Interval Training (HIIT). Background operation is limited.

**Highlights:** Second-based interval timing, Alarm and vibration alerts, Repetition counter, Saves interval settings, Suitable for HIIT, Background operation limited

**Features:** Vision Pro support

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Remove Ads | $1.99 | one-time |


### コラッツ計算機｜数列シミュレーター

[App page](https://appshunter.io/ios/app/id6766773009)

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| プレミアム | $0.49 | one-time |


## Frequently asked questions

### Is Interval Timer Sec+Sec free?

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

### Is コラッツ計算機｜数列シミュレーター free?

コラッツ計算機｜数列シミュレーター is free to download, with in-app purchases available.

### Do Interval Timer Sec+Sec or コラッツ計算機｜数列シミュレーター have ads?

Both Interval Timer Sec+Sec and コラッツ計算機｜数列シミュレーター show ads.

### Which is updated more often, Interval Timer Sec+Sec or コラッツ計算機｜数列シミュレーター?

Interval Timer Sec+Sec ships an update every 12 months, and コラッツ計算機｜数列シミュレーター weekly. Most recently, Interval Timer Sec+Sec was updated on October 29, 2026 and コラッツ計算機｜数列シミュレーター on October 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.*