# Hydrostate vs BT21 Messenger Simulator

The clearest difference is in-app purchases: BT21 Messenger Simulator at none against Hydrostate's 10. Hydrostate's advantage is iOS requirement (15.0 vs 26.2). On price, rating, ratings volume and ads there is nothing between them.

Both are free to download. Hydrostate sells 10 one-off in-app purchases. BT21 Messenger Simulator asks for nothing beyond the download.

On the App Store both sit at effectively the same score — 4.4 for Hydrostate against 4.5 for BT21 Messenger Simulator. Both are backed by a comparable volume of ratings — 13 and 8 respectively.

## The numbers

| Metric | Hydrostate | BT21 Messenger Simulator |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [4.4 (13 ratings)](https://appshunter.io/ios/app/hydrostate-water-network-3d/id6755589355/reviews) | **[4.5 (8 ratings)](https://appshunter.io/ios/app/bt21-messenger-simulator/id6758635642/reviews)** |
| Number of ratings | **13** | 8 |
| Positive reviews | 0.0% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | Yes | Yes |
| Update frequency | Every 2 weeks | — |
| Monetization | Free with in-app purchases | **Ad-supported** |
| Size | 350 MB | 193 MB |
| Requires iOS | **15.0** | 26.2 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 9+ | 4+ |
| Developer | [AAM GAMES LTD](https://appshunter.io/developer/1745519754) | [Thomas Chen](https://appshunter.io/developer/1479535275) |

## What reviewers say

### Hydrostate

[App page](https://appshunter.io/ios/app/hydrostate-water-network-3d/id6755589355)

Build and manage a city's water system by connecting pipes and optimizing flow. Solve challenging puzzles, upgrade your network, and expand your water empire in a vibrant 3D environment. Enjoy relaxing yet engaging gameplay as you ensure every building receives water.

**Highlights:** Build and connect water pipes, Manage water flow and pressure, Solve logic and planning puzzles, Upgrade and expand city water network, Experience beautiful 3D environments, Relaxing and engaging gameplay

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

**In-app purchases (10)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Get 7 Water Tanks | $0.99 | one-time |
| Cash 300k | $0.99 | one-time |
| Cash 300K | $0.99 | one-time |
| 75 Gems | $0.99 | one-time |
| Get 16 Water Tanks | $1.99 | one-time |
| Auto Cash Collector | $1.99 | one-time |
| Cash 1M | $2.99 | one-time |
| Remove Pop up ads | $2.99 | one-time |
| 1M Cash | $2.99 | one-time |
| 250 Gems | $2.99 | one-time |


### BT21 Messenger Simulator

[App page](https://appshunter.io/ios/app/bt21-messenger-simulator/id6758635642)

Engage in playful, interactive conversations with virtual characters. Choose your responses and see how they reply, creating a personalized chat experience. It's a game where your choices shape the dialogue.

**Highlights:** Interactive chat conversations, Choose your dialogue responses, Personalized chat experience, Playful and engaging gameplay, Virtual character interactions

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Hydrostate free?

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

### Is BT21 Messenger Simulator free?

BT21 Messenger Simulator is free to download, with no in-app purchases.

### Which has better reviews, Hydrostate or BT21 Messenger Simulator?

BT21 Messenger Simulator is rated higher. Hydrostate averages 4.4 out of 5 from 13 ratings, while BT21 Messenger Simulator averages 4.5 from 8 ratings.

### Do Hydrostate or BT21 Messenger Simulator have ads?

Both Hydrostate and BT21 Messenger Simulator show ads.

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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.*