# String Theory! vs 4ToDo

The clearest difference is price: String Theory! at Free against 4ToDo's $1.99. String Theory! also leads on device support (3 vs 1) and iOS requirement (15.1 vs 26.0). 4ToDo's advantage is in-app purchases (none vs 3) and ads (none vs shown).

String Theory! is free to download; 4ToDo costs $1.99 up front. String Theory! sells 3 in-app purchases, starting at $2.99 per 7 days. 4ToDo asks for nothing beyond the download.

## The numbers

| Metric | String Theory! | 4ToDo |
| --- | --- | --- |
| Price | **Free** | $1.99 |
| Rating | **[2.0 (1 ratings)](https://appshunter.io/ios/app/string-theory/id6757779491/reviews)** | — |
| Number of ratings | **1** | — |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | — | Every 6 months |
| Monetization | Free with in-app purchases | — |
| Size | 56 MB | 6 MB |
| Requires iOS | **15.1** | 26.0 |
| Devices | **iPhone, iPad, iPod** | iPhone |
| Age rating | 4+ | 4+ |
| Developer | [Synthify Inc](https://appshunter.io/developer/1089257745) | [Robert Poetzsch](https://appshunter.io/developer/1860642630) |

## What reviewers say

### String Theory!

[App page](https://appshunter.io/ios/app/string-theory/id6757779491)

This app provides a digital space to visually organize ideas, clues, and connections. Create interactive boards with photos, notes, and images, then link them with strings to uncover patterns. It's designed to help users map out complex information for various creative and analytical tasks.

**Highlights:** Unlimited detective boards, Add photos, images, and notes, Pin items freely, Connect clues with strings, Organize with tags, Distraction-free design

**Features:** macOS Compatibility

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Weekly | $2.99 | per 7 days |
| Yearly | $24.99 | per year |
| One Time | $29.99 | one-time |


### 4ToDo

[App page](https://appshunter.io/ios/app/4todo/id6760901710)

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

**In-app purchases:** none


## Frequently asked questions

### Is String Theory! free?

String Theory! is free to download, with in-app purchases available.

### Is 4ToDo free?

4ToDo costs $1.99, with no in-app purchases.

### Do String Theory! or 4ToDo have ads?

String Theory! shows ads; 4ToDo does not.

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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.*