# ISOTEC vs RattleStork

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

Both are free to download. RattleStork sells 3 in-app purchases, starting at $12.99 per month. ISOTEC asks for nothing beyond the download.

ISOTEC ships an update every 3 months, RattleStork every 3 weeks. The most recent releases landed on November 3, 2026 and November 9, 2026 respectively.

## The numbers

| Metric | ISOTEC | RattleStork |
| --- | --- | --- |
| Price | Free | Free |
| Rating | — | **[3.4 (5 ratings)](https://appshunter.io/ios/app/rattlestork-sperm-donation/id6503442456/reviews)** |
| Number of ratings | — | **5** |
| Positive reviews | — | 40.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 3 months | **Every 3 weeks** |
| Monetization | — | Free with in-app purchases |
| Size | 29 MB | 329 MB |
| Requires iOS | **15.0** | 15.6 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 4+ | 17+ |
| Developer | [ISOTEC GmbH](https://appshunter.io/developer/1476709702) | [RattleStork](https://appshunter.io/developer/1749270817) |

## What reviewers say

### ISOTEC

[App page](https://appshunter.io/ios/app/isotec/id1476709703)

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

**In-app purchases:** none


### RattleStork

[App page](https://appshunter.io/ios/app/rattlestork-sperm-donation/id6503442456)

This app facilitates sperm donation and co-parenting in the US, connecting individuals and couples with donors and co-parents. It offers a direct, clinic-free approach to family building with secure messaging and verified profiles.

**Highlights:** Sperm donation in the US, Co-parenting connections, Home insemination support, Verified donor profiles, Secure, private messaging, Clinic-free family building

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

**In-app purchases (3)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Rattlestork Premium Monthly | $12.99 | per month |
| Rattlestork Premium Quaterly | $24.99 | per 3 months |
| Rattlestork Premium Annually | $99.99 | per year |


## Frequently asked questions

### Is ISOTEC free?

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

### Is RattleStork free?

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

### Do ISOTEC or RattleStork have ads?

Neither ISOTEC nor RattleStork shows ads.

### Which is updated more often, ISOTEC or RattleStork?

ISOTEC ships an update every 3 months, and RattleStork every 3 weeks. Most recently, ISOTEC was updated on November 3, 2026 and RattleStork on November 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.*