# OB Wheels vs OB Calc (cloud)

The clearest difference is rating: OB Calc (cloud) at 5.0 against OB Wheels's 2.3. OB Calc (cloud) also leads on update cadence (every 3 months vs every 18 months). OB Wheels's advantage is in-app purchases (none vs 2) and review sentiment (20% vs 0%). On price, ads and device support there is nothing between them.

Both are free to download. OB Calc (cloud) sells 2 in-app purchases, starting at $2.99 per month. OB Wheels asks for nothing beyond the download.

OB Calc (cloud) holds the better App Store score, 5.0 against 2.3. Both are backed by a comparable volume of ratings — 15 and 5 respectively. Written reviews complicate that: 20% of OB Wheels's written reviews are positive against 0% of OB Calc (cloud)'s, so the app with the better star average is not the one people write more warmly about.

OB Wheels ships an update every 18 months, OB Calc (cloud) every 3 months. Both last shipped on October 8, 2026.

## The numbers

| Metric | OB Wheels | OB Calc (cloud) |
| --- | --- | --- |
| Price | Free | Free |
| Rating | [2.3 (15 ratings)](https://appshunter.io/ios/app/ob-wheels/id969845527/reviews) | **[5.0 (5 ratings)](https://appshunter.io/ios/app/ob-calc-cloud/id1495610465/reviews)** |
| Number of ratings | **15** | 5 |
| Positive reviews | **20.0% of reviews** | 0.0% of reviews |
| In-app purchases | **No** | Yes |
| Ads | No | No |
| Update frequency | Every 18 months | **Every 3 months** |
| Monetization | **Free** | Free with in-app purchases |
| Size | 3 MB | 14 MB |
| Requires iOS | **7.0** | 18.0 |
| Devices | iPhone, iPod | **iPhone, iPad, Mac** |
| Age rating | 17+ | 4+ |
| Developer | [Joshua D. steinberg](https://appshunter.io/developer/374154837) | [Glen Botha](https://appshunter.io/developer/943181947) |

## What reviewers say

### OB Wheels

[App page](https://appshunter.io/ios/app/ob-wheels/id969845527)

This app calculates due dates, gestational age, and reconciles sonogram and LMP dates using a digital OB wheel and calendar. It offers a familiar interactive wheel for precise date calculations, accounting for leap years.

**Highlights:** Calendar calculator for EDD/EDC, Gestational age calculation, Interactive digital OB wheel, Reconciliation of due dates, Leap year accuracy

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

**In-app purchases:** none


### OB Calc (cloud)

[App page](https://appshunter.io/ios/app/ob-calc-cloud/id1495610465)

This medical app helps obstetricians efficiently calculate key patient test date windows. It offers multiple calculation methods and allows for saving patient data and generating PDF reports. A free trial is available, followed by a subscription for full access.

**Highlights:** LMP, EDC, Ultrasound, CRL, and IVF calculations, Customizable test date ranges, Cross-device data syncing, PDF report generation, Save individual patient data

**Features:** Vision Pro support

**In-app purchases (2)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Monthly Subscription | $2.99 | per month |
| Premium (Annual) | $29.99 | per year |


## Frequently asked questions

### Is OB Wheels free?

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

### Is OB Calc (cloud) free?

OB Calc (cloud) is free to download, with in-app purchases available.

### Which has better reviews, OB Wheels or OB Calc (cloud)?

OB Calc (cloud) is rated higher. OB Wheels averages 2.3 out of 5 from 15 ratings, while OB Calc (cloud) averages 5.0 from 5 ratings.

### Do OB Wheels or OB Calc (cloud) have ads?

Neither OB Wheels nor OB Calc (cloud) shows ads.

### Which is updated more often, OB Wheels or OB Calc (cloud)?

OB Wheels ships an update every 18 months, and OB Calc (cloud) every 3 months. Most recently, OB Wheels was updated on October 8, 2026 and OB Calc (cloud) on October 8, 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.*