# Parallel Books vs RidoBooks

The clearest difference is in-app purchases: Parallel Books at none against RidoBooks's 12. Parallel Books also leads on ads (none vs shown). RidoBooks's advantage is update cadence (monthly vs every 3 months). On price, device support and iOS requirement there is nothing between them.

Both are free to download. RidoBooks sells 12 in-app purchases, starting at $3.99 per 7 days. Parallel Books asks for nothing beyond the download.

Parallel Books ships an update every 3 months, RidoBooks monthly. The most recent releases landed on October 9, 2026 and September 23, 2026 respectively.

## The numbers

| Metric | Parallel Books | RidoBooks |
| --- | --- | --- |
| Price | Free | Free |
| Positive reviews | 40.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 3 months | **Monthly** |
| Monetization | Free | — |
| Size | 2 MB | 78 MB |
| Requires iOS | 15.6 | **15.0** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 12+ | 4+ |
| Developer | [High Tea IT Limited](https://appshunter.io/developer/1045596663) | [Rido Lang Sp Z O.O.](https://appshunter.io/developer/1809375471) |

## What reviewers say

### Parallel Books

[App page](https://appshunter.io/ios/app/parallel-books/id1045596664)

Learn a new language by reading books with side-by-side translations. This app keeps translations synchronized as you read, allowing for full immersion. Easily switch between display modes and add notes for a personalized learning experience.

**Highlights:** Dual language display, Synchronized translations, Adjustable display modes, Searchable notes, Day/night themes, Highlighting

**Features:** macOS Compatibility

**In-app purchases:** none


### RidoBooks

[App page](https://appshunter.io/ios/app/ridobooks/id6744822677)

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

**In-app purchases (12)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Weekly | $3.99 | per 7 days |
| RidoBooks Free Trial | $4.99 | per 7 days |
| Monthly | $7.99 | per month |
| Monthly Pro | $9.99 | per month |
| Premium Monthly | $9.99 | per month |
| Quarterly | $14.99 | per 3 months |
| Quarterly | $17.99 | per 3 months |
| Semiannual | $17.99 | per 6 months |
| Semiannual Pro | $24.99 | per 6 months |
| Yearly | $29.99 | per year |
| Premium Yearly | $29.99 | per year |
| Yearly Pro | $39.99 | per year |


## Frequently asked questions

### Is Parallel Books free?

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

### Is RidoBooks free?

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

### Do Parallel Books or RidoBooks have ads?

RidoBooks shows ads; Parallel Books does not.

### Which is updated more often, Parallel Books or RidoBooks?

Parallel Books ships an update every 3 months, and RidoBooks monthly. Most recently, Parallel Books was updated on October 9, 2026 and RidoBooks on September 23, 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.*