# Periodic Table Memorization vs marrow

The clearest difference is in-app purchases: marrow at none against Periodic Table Memorization's 3. marrow also leads on ads (none vs shown) and update cadence (every 3 days vs every 3 weeks). On price, device support and iOS requirement there is nothing between them.

Both are free to download. Periodic Table Memorization sells 3 in-app purchases, starting at $1.99 per month. marrow asks for nothing beyond the download.

Periodic Table Memorization ships an update every 3 weeks, marrow every 3 days. The most recent releases landed on October 1, 2026 and September 28, 2026 respectively.

## The numbers

| Metric | Periodic Table Memorization | marrow |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[4.0 (3 ratings)](https://appshunter.io/ios/app/periodic-table-memorization/id6776222961/reviews)** | — |
| Number of ratings | **3** | — |
| In-app purchases | Yes | **No** |
| Ads | Yes | **No** |
| Update frequency | Every 3 weeks | **Every 3 days** |
| Monetization | Free with in-app purchases | — |
| Size | 18 MB | 40 MB |
| Requires iOS | 17.0 | **16.4** |
| Devices | iPhone, iPad | iPhone, iPad |
| Age rating | 4+ | 4+ |
| Developer | [YU KORIKI](https://appshunter.io/developer/6776222963) | [Pratyush Saxena](https://appshunter.io/developer/1896770612) |

## What reviewers say

### Periodic Table Memorization

[App page](https://appshunter.io/ios/app/periodic-table-memorization/id6776222961)

Master element symbols and atomic numbers with interactive study modes. Build habits with daily streaks and reminders, track progress with charts, and prepare for chemistry exams. Works offline and offers a free trial.

**Highlights:** Four study modes: flashcards, quiz, fill-in-the-blank, puzzle, Daily streaks and reminders, Progress tracking charts, Offline functionality, Exam preparation for chemistry, Memorize element symbols and atomic numbers

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly Premium | $1.99 | per month |
| Premium Yearly | $22.99 | per year |
| Premium lifetime | $1.99 | one-time |


### marrow

[App page](https://appshunter.io/ios/app/marrow-scroll-to-learn/id6791669414)

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

**In-app purchases:** none


## Frequently asked questions

### Is Periodic Table Memorization free?

Periodic Table Memorization is free to download, with in-app purchases available.

### Is marrow free?

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

### Do Periodic Table Memorization or marrow have ads?

Periodic Table Memorization shows ads; marrow does not.

### Which is updated more often, Periodic Table Memorization or marrow?

Periodic Table Memorization ships an update every 3 weeks, and marrow every 3 days. Most recently, Periodic Table Memorization was updated on October 1, 2026 and marrow on September 28, 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.*