# SecondBrain AI Assistant vs Otto AI

The clearest difference is update cadence: SecondBrain AI Assistant at daily against Otto AI's every 9 days. On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. SecondBrain AI Assistant sells 2 in-app purchases, starting at $9.99 per month and Otto AI sells 6 in-app purchases, starting at $1.99 per 7 days. Whichever you choose, the download price is not the number that matters.

SecondBrain AI Assistant ships an update daily, Otto AI every 9 days. The most recent releases landed on October 17, 2026 and October 24, 2026 respectively.

## The numbers

| Metric | SecondBrain AI Assistant | Otto AI |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | **Daily** | Every 9 days |
| Size | 23 MB | 12 MB |
| Requires iOS | 15.0 | 15.0 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [BUILD TO CONNECT LTD](https://appshunter.io/developer/6778076361) | [Arghyadeep Karmakar](https://appshunter.io/developer/6790373278) |

## What reviewers say

### SecondBrain AI Assistant

[App page](https://appshunter.io/ios/app/secondbrain-ai-assistant/id6778076359)

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

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Second Brain Pro Monthly | $9.99 | per month |
| Second Brain Pro Annual | $69.99 | per year |


### Otto AI

[App page](https://appshunter.io/ios/app/otto-ai-email-assistant/id6790373276)

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

**In-app purchases (6)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Otto Plus | $1.99 | per 7 days |
| Otto Plus | $4.99 | per month |
| Otto Pro | $5.99 | per 7 days |
| Otto Pro | $14.99 | per month |
| Otto Plus | $39.99 | per year |
| Otto Pro | $119.99 | per year |


## Frequently asked questions

### Is SecondBrain AI Assistant free?

SecondBrain AI Assistant is free to download, with in-app purchases available.

### Is Otto AI free?

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

### Do SecondBrain AI Assistant or Otto AI have ads?

Neither SecondBrain AI Assistant nor Otto AI shows ads.

### Which is updated more often, SecondBrain AI Assistant or Otto AI?

SecondBrain AI Assistant ships an update daily, and Otto AI every 9 days. Most recently, SecondBrain AI Assistant was updated on October 17, 2026 and Otto AI on October 24, 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.*