# Building a Second Brain vs fenel

The clearest difference is update cadence: fenel at every 6 days against Building a Second Brain's every 4 months. Building a Second Brain's advantage is iOS requirement (16.4 vs 18.0). 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.

Building a Second Brain ships an update every 4 months, fenel every 6 days. The most recent releases landed on October 13, 2026 and October 17, 2026 respectively.

## The numbers

| Metric | Building a Second Brain | fenel |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.7 (12 ratings)](https://appshunter.io/ios/app/building-a-second-brain/id6744942882/reviews)** | — |
| Number of ratings | **12** | — |
| Positive reviews | 50.0% of reviews | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | Every 4 months | **Every 6 days** |
| Monetization | Free | — |
| Size | 90 MB | 65 MB |
| Requires iOS | **16.4** | 18.0 |
| Devices | **iPhone, iPad** | iPhone |
| Age rating | 17+ | 17+ |
| Developer | [Forte Labs, LLC](https://appshunter.io/developer/1810064260) | [Resiin Inc](https://appshunter.io/developer/1884704759) |

## What reviewers say

### Building a Second Brain

[App page](https://appshunter.io/ios/app/building-a-second-brain/id6744942882)

This app helps you manage information overload and achieve your goals through personal knowledge management. Connect with a community focused on productivity and digital organization for a more peaceful and purposeful life.

**Highlights:** PARA Method Mini-Course, Community Hub, Exclusive event invitations, Notetaking and creativity resources, Gateway to comprehensive courses

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

**In-app purchases:** none


### fenel

[App page](https://appshunter.io/ios/app/fenel/id6760489144)

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

**In-app purchases:** none


## Frequently asked questions

### Is Building a Second Brain free?

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

### Is fenel free?

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

### Do Building a Second Brain or fenel have ads?

Neither Building a Second Brain nor fenel shows ads.

### Which is updated more often, Building a Second Brain or fenel?

Building a Second Brain ships an update every 4 months, and fenel every 6 days. Most recently, Building a Second Brain was updated on October 13, 2026 and fenel on October 17, 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.*