# trifit Strength Log vs ChironMotion IMU

The clearest difference is update cadence: trifit Strength Log at fortnightly against ChironMotion IMU's every 2 months. ChironMotion IMU's advantage is iOS requirement (18.0 vs 26.0). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. trifit Strength Log sells 1 in-app purchase, starting at $1.99 per month and ChironMotion IMU sells 2 in-app purchases, starting at $3.99 per month. Whichever you choose, the download price is not the number that matters.

trifit Strength Log ships an update fortnightly, ChironMotion IMU every 2 months. The most recent releases landed on October 28, 2026 and October 25, 2026 respectively.

## The numbers

| Metric | trifit Strength Log | ChironMotion IMU |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | **Fortnightly** | Every 2 months |
| Size | 119 MB | 21 MB |
| Requires iOS | 26.0 | **18.0** |
| Devices | iPhone, Apple Watch | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [TeHan Liao](https://appshunter.io/developer/1745243045) | [Yi-Fu Chen](https://appshunter.io/developer/1873701789) |

## What reviewers say

### trifit Strength Log

[App page](https://appshunter.io/ios/app/trifit-strength-log/id6744907298)

**Features:** Apple Watch app

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| trifit 創始者方案 | $1.99 | per month |


### ChironMotion IMU

[App page](https://appshunter.io/ios/app/chironmotion-imu/id6758951844)

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pro Monthly Plan | $3.99 | per month |
| Pro Yearly Plan | $39.99 | per year |


## Frequently asked questions

### Is trifit Strength Log free?

trifit Strength Log is free to download, with in-app purchases available.

### Is ChironMotion IMU free?

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

### Do trifit Strength Log or ChironMotion IMU have ads?

Neither trifit Strength Log nor ChironMotion IMU shows ads.

### Which is updated more often, trifit Strength Log or ChironMotion IMU?

trifit Strength Log ships an update fortnightly, and ChironMotion IMU every 2 months. Most recently, trifit Strength Log was updated on October 28, 2026 and ChironMotion IMU 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.*