# Learn DBMS vs Database Keys and Constraints

The clearest difference is in-app purchases: Database Keys and Constraints at none against Learn DBMS's 1. On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. Learn DBMS sells 1 one-off in-app purchase. Database Keys and Constraints asks for nothing beyond the download.

## The numbers

| Metric | Learn DBMS | Database Keys and Constraints |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | Every 16 months | — |
| Size | 28 MB | 38 MB |
| Requires iOS | 15.1 | 15.1 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Ghumman Tech LLC](https://appshunter.io/developer/1671347750) | [AFTW LLC](https://appshunter.io/developer/1886356149) |

## What reviewers say

### Learn DBMS

[App page](https://appshunter.io/ios/app/learn-dbms/id6446442808)

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Remove Ads | $9.99 | one-time |


### Database Keys and Constraints

[App page](https://appshunter.io/ios/app/database-keys-and-constraints/id6773622183)

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

**In-app purchases:** none


## Frequently asked questions

### Is Learn DBMS free?

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

### Is Database Keys and Constraints free?

Database Keys and Constraints is free to download, with no in-app purchases.

### Do Learn DBMS or Database Keys and Constraints have ads?

Neither Learn DBMS nor Database Keys and Constraints shows 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.*