# do!bookⅡ vs O

The clearest difference is update cadence: do!bookⅡ at every 2 months against O's every 17 months. do!bookⅡ also leads on iOS requirement (9.0 vs 15.5). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

do!bookⅡ ships an update every 2 months, O every 17 months. The most recent releases landed on September 14, 2026 and May 16, 2026 respectively.

## The numbers

| Metric | do!bookⅡ | O |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 2 months** | Every 17 months |
| Size | 21 MB | 1 MB |
| Requires iOS | **9.0** | 15.5 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Digital Office  Japan  Inc.](https://appshunter.io/developer/348581782) | [O-TECH JAPAN](https://appshunter.io/developer/1219186631) |

## What reviewers say

### do!bookⅡ

[App page](https://appshunter.io/ios/app/dobook/id599472647)

**Features:** macOS Compatibility

**In-app purchases:** none


### O

[App page](https://appshunter.io/ios/app/o-techpos/id1631489398)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is do!bookⅡ free?

do!bookⅡ is free to download, with no in-app purchases.

### Is O free?

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

### Do do!bookⅡ or O have ads?

Neither do!bookⅡ nor O shows ads.

### Which is updated more often, do!bookⅡ or O?

do!bookⅡ ships an update every 2 months, and O every 17 months. Most recently, do!bookⅡ was updated on September 14, 2026 and O on May 16, 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.*