# SmartWatch BT Sync vs ChangeUnits2

The clearest difference is price: SmartWatch BT Sync at Free against ChangeUnits2's $0.99. SmartWatch BT Sync also leads on ratings volume (227 vs 1). ChangeUnits2's advantage is rating (5.0 vs 3.8) and in-app purchases (none vs 2). On ads, device support and iOS requirement there is nothing between them.

SmartWatch BT Sync is free to download; ChangeUnits2 costs $0.99 up front. SmartWatch BT Sync sells 2 in-app purchases, starting at $1.99 per 7 days. ChangeUnits2 asks for nothing beyond the download.

ChangeUnits2 holds the better App Store score, 5.0 against 3.8. That said, the two scores are not equally well evidenced: SmartWatch BT Sync has 227 ratings behind it against 1, so its average is the more settled of the two.

SmartWatch BT Sync ships an update every 3 months, ChangeUnits2 every 4 weeks. The most recent releases landed on September 23, 2026 and June 1, 2026 respectively.

## The numbers

| Metric | SmartWatch BT Sync | ChangeUnits2 |
| --- | --- | --- |
| Price | **Free** | $0.99 |
| Rating | [3.8 (227 ratings)](https://appshunter.io/ios/app/smartwatch-bt-sync/id1643638475/reviews) | **[5.0 (1 ratings)](https://appshunter.io/ios/app/changeunits2/id1661260714/reviews)** |
| Number of ratings | **227** | 1 |
| Positive reviews | 18.2% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 3 months | **Every 4 weeks** |
| Monetization | **Free with in-app purchases** | Paid |
| Size | 44 MB | 17 MB |
| Requires iOS | **14.1** | 15.6 |
| Devices | iPhone, iPod | **iPhone, iPad, iPod** |
| Age rating | 4+ | 4+ |
| Developer | [AN VIET COMPANY LIMITED](https://appshunter.io/developer/1642433347) | [Jack McCormack](https://appshunter.io/developer/1658121467) |

## What reviewers say

### SmartWatch BT Sync

[App page](https://appshunter.io/ios/app/smartwatch-bt-sync/id1643638475)

Connect your Bluetooth-enabled smartwatch to your smartphone to track, sync, and transfer all your health and activity data. Map your routes for activities like running and trekking.

**Highlights:** Connect smart watch to smartphone, Track, sync, and transfer data, Map activity routes, Supports smartbands and BT smartwatches, Bluetooth connectivity

**Features:** macOS Compatibility

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Access all for weekly | $1.99 | per 7 days |
| Access all for yearly | $19.99 | per year |


### ChangeUnits2

[App page](https://appshunter.io/ios/app/changeunits2/id1661260714)

This powerful utility app offers lightning-fast and accurate unit conversions for a wide range of needs. It includes advanced math functions, currency exchange, time zone tracking, and even chemical equation balancing. Designed for professionals and everyday users alike, it works offline and remembers your last calculations.

**Highlights:** Extreme speed and accuracy, Offline functionality, Currency exchange converter, Global time zone tracking, Advanced math functions, Chemical equation balancing, Last 33 calculations remembered

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is SmartWatch BT Sync free?

SmartWatch BT Sync is free to download, with in-app purchases available.

### Is ChangeUnits2 free?

ChangeUnits2 costs $0.99, with no in-app purchases.

### Which has better reviews, SmartWatch BT Sync or ChangeUnits2?

ChangeUnits2 is rated higher. SmartWatch BT Sync averages 3.8 out of 5 from 227 ratings, while ChangeUnits2 averages 5.0 from 1 ratings.

### Do SmartWatch BT Sync or ChangeUnits2 have ads?

Neither SmartWatch BT Sync nor ChangeUnits2 shows ads.

### Which is updated more often, SmartWatch BT Sync or ChangeUnits2?

SmartWatch BT Sync ships an update every 3 months, and ChangeUnits2 every 4 weeks. Most recently, SmartWatch BT Sync was updated on September 23, 2026 and ChangeUnits2 on June 1, 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.*