# Cactus vs NumbBrain

The clearest difference is update cadence: Cactus at weekly against NumbBrain's every 4 months. On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Cactus sells 1 in-app purchase, starting at $4.99 per month and NumbBrain sells 3 in-app purchases, starting at $0.99 per month. Whichever you choose, the download price is not the number that matters.

Cactus ships an update weekly, NumbBrain every 4 months. The most recent releases landed on July 24, 2026 and September 15, 2026 respectively.

## The numbers

| Metric | Cactus | NumbBrain |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (2 ratings)](https://appshunter.io/ios/app/cactus-ai-memory-sidekick/id6748361695/reviews)** | — |
| Number of ratings | **2** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | Yes | Yes |
| Ads | No | No |
| Update frequency | **Weekly** | Every 4 months |
| Monetization | Freemium | — |
| Size | 2 MB | 14 MB |
| Requires iOS | 17.0 | 17.0 |
| Devices | **iPhone, iPad** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Feidong Song](https://appshunter.io/developer/1792424713) | [笛 姜](https://appshunter.io/developer/1561507357) |

## What reviewers say

### Cactus

[App page](https://appshunter.io/ios/app/cactus-ai-memory-sidekick/id6748361695)

An AI-powered assistant designed to help you manage your day, capture ideas, and organize tasks. It offers natural language interaction, voice input, and secure cloud synchronization for seamless productivity.

**Highlights:** AI-powered assistant, Natural language interaction, Voice capture for ideas, Task organization, Schedule management, Secure cloud sync

**Features:** macOS Compatibility

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Premium plan. | $4.99 | per month |


### NumbBrain

[App page](https://appshunter.io/ios/app/numbbrain-screen-time-control/id6751564003)

**Features:** macOS Compatibility, Family Sharing

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly Premium | $0.99 | per month |
| Annual Premium | $2.99 | per year |
| Lifetime Premium | $5.99 | one-time |


## Frequently asked questions

### Is Cactus free?

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

### Is NumbBrain free?

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

### Do Cactus or NumbBrain have ads?

Neither Cactus nor NumbBrain shows ads.

### Which is updated more often, Cactus or NumbBrain?

Cactus ships an update weekly, and NumbBrain every 4 months. Most recently, Cactus was updated on July 24, 2026 and NumbBrain on September 15, 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.*