# HydraCal vs Dopamo

The clearest difference is in-app purchases: HydraCal at none against Dopamo's 2. Dopamo's advantage is update cadence (every 3 days vs every 4 weeks). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. Dopamo sells 2 one-off in-app purchases. HydraCal asks for nothing beyond the download.

HydraCal ships an update every 4 weeks, Dopamo every 3 days. The most recent releases landed on September 28, 2026 and October 3, 2026 respectively.

## The numbers

| Metric | HydraCal | Dopamo |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 4 weeks | **Every 3 days** |
| Size | 39 MB | 41 MB |
| Requires iOS | **15.1** | 15.6 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 17+ | 4+ |
| Developer | [Daniel Mitchell](https://appshunter.io/developer/1837385073) | [Simon Gobes](https://appshunter.io/developer/6790823891) |

## What reviewers say

### HydraCal

[App page](https://appshunter.io/ios/app/hydracal/id6751882234)

**Features:** macOS Compatibility

**In-app purchases:** none


### Dopamo

[App page](https://appshunter.io/ios/app/dopamo/id6790830421)

**Features:** macOS Compatibility

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Extra Family Member | $0.99 | one-time |
| Streak Restore | $0.99 | one-time |


## Frequently asked questions

### Is HydraCal free?

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

### Is Dopamo free?

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

### Do HydraCal or Dopamo have ads?

Neither HydraCal nor Dopamo shows ads.

### Which is updated more often, HydraCal or Dopamo?

HydraCal ships an update every 4 weeks, and Dopamo every 3 days. Most recently, HydraCal was updated on September 28, 2026 and Dopamo on October 3, 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.*