# TDMS vs Shaft Alignment Calculator

The clearest difference is price: TDMS at Free against Shaft Alignment Calculator's $5.99. Shaft Alignment Calculator's advantage is update cadence (every 2 days vs every 26 months) and iOS requirement (13.0 vs 15.0). On ads, in-app purchases and device support there is nothing between them.

TDMS is free to download; Shaft Alignment Calculator costs $5.99 up front. Neither carries in-app purchases, so what you see is what you pay.

TDMS ships an update every 26 months, Shaft Alignment Calculator every 2 days. The most recent releases landed on October 25, 2026 and October 20, 2026 respectively.

## The numbers

| Metric | TDMS | Shaft Alignment Calculator |
| --- | --- | --- |
| Price | **Free** | $5.99 |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 26 months | **Every 2 days** |
| Size | 4 MB | 20 MB |
| Requires iOS | 15.0 | **13.0** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [TOHNICHI MFG.CO., LTD.](https://appshunter.io/developer/1609166229) | [Eiji Shinohara](https://appshunter.io/developer/1894855517) |

## What reviewers say

### TDMS

[App page](https://appshunter.io/ios/app/tdms/id6479276073)

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

**In-app purchases:** none


### Shaft Alignment Calculator

[App page](https://appshunter.io/ios/app/shaft-alignment-calculator/id6762618674)

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

**In-app purchases:** none


## Frequently asked questions

### Is TDMS free?

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

### Is Shaft Alignment Calculator free?

Shaft Alignment Calculator costs $5.99, with no in-app purchases.

### Do TDMS or Shaft Alignment Calculator have ads?

Neither TDMS nor Shaft Alignment Calculator shows ads.

### Which is updated more often, TDMS or Shaft Alignment Calculator?

TDMS ships an update every 26 months, and Shaft Alignment Calculator every 2 days. Most recently, TDMS was updated on October 25, 2026 and Shaft Alignment Calculator on October 20, 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.*