# Second Brain SB vs AI Prompt Builder

The clearest difference is in-app purchases: Second Brain SB at none against AI Prompt Builder's 1. AI Prompt Builder's advantage is update cadence (every 3 months vs every 41 months). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. AI Prompt Builder sells 1 one-off in-app purchase. Second Brain SB asks for nothing beyond the download.

Second Brain SB ships an update every 41 months, AI Prompt Builder every 3 months. The most recent releases landed on October 30, 2026 and October 27, 2026 respectively.

## The numbers

| Metric | Second Brain SB | AI Prompt Builder |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 41 months | **Every 3 months** |
| Size | 21 MB | 6 MB |
| Requires iOS | **15.0** | 16.1 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [Gianlucca Vick](https://appshunter.io/developer/1691417067) | [Eduardo Dominguez Menendez](https://appshunter.io/developer/1697629661) |

## What reviewers say

### Second Brain SB

[App page](https://appshunter.io/ios/app/second-brain-sb/id6449985684)

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

**In-app purchases:** none


### AI Prompt Builder

[App page](https://appshunter.io/ios/app/ai-prompt-builder/id6737697088)

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Unlimited prompts + Remove Ads | $4.99 | one-time |


## Frequently asked questions

### Is Second Brain SB free?

Second Brain SB is free to download, with no in-app purchases.

### Is AI Prompt Builder free?

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

### Do Second Brain SB or AI Prompt Builder have ads?

Neither Second Brain SB nor AI Prompt Builder shows ads.

### Which is updated more often, Second Brain SB or AI Prompt Builder?

Second Brain SB ships an update every 41 months, and AI Prompt Builder every 3 months. Most recently, Second Brain SB was updated on October 30, 2026 and AI Prompt Builder on October 27, 2026.

---

*Compared by [AppsHunter](https://appshunter.io/) from daily US App Store data. Review summaries are generated from verbatim App Store reviews.*