# PrepFlex vs String Theory!

The clearest difference is in-app purchases: PrepFlex at none against String Theory!'s 3. PrepFlex also leads on ads (none vs shown). On price, device support and iOS requirement there is nothing between them.

Both are free to download. String Theory! sells 3 in-app purchases, starting at $2.99 per 7 days. PrepFlex asks for nothing beyond the download.

## The numbers

| Metric | PrepFlex | String Theory! |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (5 ratings)](https://appshunter.io/ios/app/prepflex-study-optimizer/id6754576477/reviews)** | — |
| Number of ratings | **5** | — |
| Positive reviews | 100.0% of reviews | — |
| In-app purchases | **No** | Yes |
| Ads | **No** | Yes |
| Update frequency | Every 10 months | — |
| Monetization | Free | — |
| Size | 25 MB | 56 MB |
| Requires iOS | 15.6 | **15.1** |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 4+ |
| Developer | [Rajat Aggarwal](https://appshunter.io/developer/1849009713) | [Synthify Inc](https://appshunter.io/developer/1089257745) |

## What reviewers say

### PrepFlex

[App page](https://appshunter.io/ios/app/prepflex-study-optimizer/id6754576477)

This app creates personalized study plans from your available time and topics. It helps students organize last-minute study sessions into effective, time-balanced schedules tailored to their needs. The app focuses on efficiency with no sign-ins or distractions.

**Highlights:** Create personalized study plans, Tailored to available time, Add and weight study topics, Set confidence levels for topics, Local data storage for privacy, Distraction-free study environment

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

**In-app purchases:** none


### String Theory!

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

**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 |


## Frequently asked questions

### Is PrepFlex free?

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

### Is String Theory! free?

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

### Do PrepFlex or String Theory! have ads?

String Theory! shows ads; PrepFlex 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.*