# OB ToolBox vs Black River Supply

The clearest difference is update cadence: OB ToolBox at every 3 weeks against Black River Supply's every 6 months. OB ToolBox also leads on iOS requirement (13.0 vs 15.6). On price, ads, in-app purchases and device support there is nothing between them.

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

OB ToolBox ships an update every 3 weeks, Black River Supply every 6 months. The most recent releases landed on September 21, 2026 and October 7, 2026 respectively.

## The numbers

| Metric | OB ToolBox | Black River Supply |
| --- | --- | --- |
| Price | Free | Free |
| Rating | **[5.0 (2 ratings)](https://appshunter.io/ios/app/ob-toolbox/id1565667366/reviews)** | — |
| Number of ratings | **2** | — |
| In-app purchases | No | No |
| Ads | No | No |
| Update frequency | **Every 3 weeks** | Every 6 months |
| Monetization | Free | — |
| Size | 56 MB | 9 MB |
| Requires iOS | **13.0** | 15.6 |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Age rating | 12+ | 17+ |
| Developer | [Frederick Blair](https://appshunter.io/developer/1565667368) | [Black River Supply Company LLC](https://appshunter.io/developer/1822636560) |

## What reviewers say

### OB ToolBox

[App page](https://appshunter.io/ios/app/ob-toolbox/id1565667366)

This app offers a quick reference for essential medical values related to fetal growth, amniotic fluid, and Doppler indices. It includes calculators for preterm birth prediction, cesarean risk, and risk of stillbirth or miscarriage.

**Highlights:** Fetal growth reference values, Estimated fetal weight calculator, Amniotic fluid and Doppler indices, Bishop score reference, Preterm birth predictor, Cesarean risk calculator, Stillbirth and miscarriage risk calculators

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

**In-app purchases:** none


### Black River Supply

[App page](https://appshunter.io/ios/app/black-river-supply/id6747728302)

**Features:** macOS Compatibility

**In-app purchases:** none


## Frequently asked questions

### Is OB ToolBox free?

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

### Is Black River Supply free?

Black River Supply is free to download, with no in-app purchases.

### Do OB ToolBox or Black River Supply have ads?

Neither OB ToolBox nor Black River Supply shows ads.

### Which is updated more often, OB ToolBox or Black River Supply?

OB ToolBox ships an update every 3 weeks, and Black River Supply every 6 months. Most recently, OB ToolBox was updated on September 21, 2026 and Black River Supply on October 7, 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.*