# GetPrincipia vs SolvedBooks

The clearest difference is in-app purchases: SolvedBooks at none against GetPrincipia's 2. GetPrincipia's advantage is ads (none vs shown). On price, device support and iOS requirement there is nothing between them.

Both are free to download. GetPrincipia sells 2 in-app purchases, starting at $6.99 per month. SolvedBooks asks for nothing beyond the download.

## The numbers

| Metric | GetPrincipia | SolvedBooks |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | **No** |
| Ads | **No** | Yes |
| Update frequency | Every 2 months | — |
| Size | 38 MB | 36 MB |
| Requires iOS | 15.1 | 15.1 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Axiom 38 LLC](https://appshunter.io/developer/1887968723) | [YAT MAN WONG](https://appshunter.io/developer/1895251417) |

## What reviewers say

### GetPrincipia

[App page](https://appshunter.io/ios/app/getprincipia/id6761139348)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly | $6.99 | per month |
| Annual | $44.99 | per year |


### SolvedBooks

[App page](https://appshunter.io/ios/app/solvedbooks/id6764142832)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is GetPrincipia free?

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

### Is SolvedBooks free?

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

### Do GetPrincipia or SolvedBooks have ads?

SolvedBooks shows ads; GetPrincipia does not.

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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.*