# Book2App vs Liminal AI

The clearest difference is in-app purchases: Liminal AI at none against Book2App's 3. Liminal AI also leads on ads (none vs shown). Book2App's advantage is iOS requirement (11.0 vs 18). On price, update cadence and device support there is nothing between them.

Both are free to download. Book2App sells 3 one-off in-app purchases. Liminal AI asks for nothing beyond the download.

Book2App ships an update every 3 months, Liminal AI every 2 months. The most recent releases landed on October 8, 2026 and October 19, 2026 respectively.

## The numbers

| Metric | Book2App | Liminal AI |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[5.0 (1 ratings)](https://appshunter.io/ios/app/liminal-ai/id6754858160/reviews)** |
| Number of ratings | — | **1** |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | Every 3 months | **Every 2 months** |
| Monetization | — | Free |
| Size | 22 MB | 34 MB |
| Requires iOS | **11.0** | 18 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 17+ |
| Developer | [Ipsilon Developments Inc](https://appshunter.io/developer/1003755058) | [Liminal AI Inc.](https://appshunter.io/developer/1792552096) |

## What reviewers say

### Book2App

[App page](https://appshunter.io/ios/app/book2app/id1488678677)

**Features:** macOS Compatibility

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| 1 Credit Recharge | $1.99 | one-time |
| 2 Credits Recharge | $3.99 | one-time |
| 10 Credits Recharge | $19.99 | one-time |


### Liminal AI

[App page](https://appshunter.io/ios/app/liminal-ai/id6754858160)

This platform provides secure, unlimited access to leading AI models for regulated enterprises. It ensures data protection and compliance while enabling seamless AI integration into workflows. Users can build custom assistants and gain insights into AI usage for business value.

**Highlights:** Secure access to leading AI models, Automatic sensitive data detection and masking, Centralized AI governance and oversight, Integration with internal data sources (RAG), Customizable multi-model AI assistants, AI usage insights and ROI measurement

**Features:** Vision Pro support

**In-app purchases:** none


## Frequently asked questions

### Is Book2App free?

Book2App is free to download, with in-app purchases available.

### Is Liminal AI free?

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

### Do Book2App or Liminal AI have ads?

Book2App shows ads; Liminal AI does not.

### Which is updated more often, Book2App or Liminal AI?

Book2App ships an update every 3 months, and Liminal AI every 2 months. Most recently, Book2App was updated on October 8, 2026 and Liminal AI on October 19, 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.*