# Cytokine vs E365

The clearest difference is in-app purchases: E365 at none against Cytokine's 4. Cytokine's advantage is update cadence (every 3 months vs every 17 months). On price, ads, device support and iOS requirement there is nothing between them.

Both are free to download. Cytokine sells 4 one-off in-app purchases. E365 asks for nothing beyond the download.

Cytokine ships an update every 3 months, E365 every 17 months. The most recent releases landed on September 13, 2026 and September 9, 2026 respectively.

## The numbers

| Metric | Cytokine | E365 |
| --- | --- | --- |
| Price | Free | Free |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Every 3 months** | Every 17 months |
| Size | 36 MB | 25 MB |
| Requires iOS | **15.1** | 15.6 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 17+ | 17+ |
| Developer | [Make Differentials](https://appshunter.io/developer/1655097872) | [EDUCATIVE TECHNOLOGIES](https://appshunter.io/developer/1699379688) |

## What reviewers say

### Cytokine

[App page](https://appshunter.io/ios/app/cytokine/id6444517018)

**Features:** Vision Pro support

**In-app purchases (4)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Pro Plan \| Primary Care | $24.99 | one-time |
| Super Plan | $29.99 | one-time |
| The Surgical Blueprint | $29.99 | one-time |
| Pro Plan | $39.99 | one-time |


### E365

[App page](https://appshunter.io/ios/app/e365/id6453484867)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is Cytokine free?

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

### Is E365 free?

E365 is free to download, with no in-app purchases.

### Do Cytokine or E365 have ads?

Neither Cytokine nor E365 shows ads.

### Which is updated more often, Cytokine or E365?

Cytokine ships an update every 3 months, and E365 every 17 months. Most recently, Cytokine was updated on September 13, 2026 and E365 on September 9, 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.*