# Watt vs SunSync

The clearest difference is in-app purchases: Watt at none against SunSync's 2. Watt also leads on update cadence (every 10 days vs every 3 weeks) and iOS requirement (12.0 vs 17.6). On price, ads and device support there is nothing between them.

Both are free to download. SunSync sells 2 in-app purchases, starting at $1.99 per year. Watt asks for nothing beyond the download.

Watt ships an update every 10 days, SunSync every 3 weeks. The most recent releases landed on November 9, 2026 and November 5, 2026 respectively.

## The numbers

| Metric | Watt | SunSync |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | **Every 10 days** | Every 3 weeks |
| Size | 82 MB | 25 MB |
| Requires iOS | **12.0** | 17.6 |
| Devices | **iPhone, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Adrian Veliman](https://appshunter.io/developer/1850800144) | [Marta Rodriguez](https://appshunter.io/developer/1873973295) |

## What reviewers say

### Watt

[App page](https://appshunter.io/ios/app/watt-energy-planner/id6759226344)

**In-app purchases:** none


### SunSync

[App page](https://appshunter.io/ios/app/sunsync-circadian-tracker/id6762293528)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Year | $1.99 | per year |
| Lifetime | $2.99 | one-time |


## Frequently asked questions

### Is Watt free?

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

### Is SunSync free?

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

### Do Watt or SunSync have ads?

Neither Watt nor SunSync shows ads.

### Which is updated more often, Watt or SunSync?

Watt ships an update every 10 days, and SunSync every 3 weeks. Most recently, Watt was updated on November 9, 2026 and SunSync on November 5, 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.*