# OB Wheels

> Medical app for pregnancy due date calculation and gestational age tracking. (iPhone/iPad app by Joshua D. steinberg.)

- Source: https://appshunter.io/ios/app/ob-wheels/id969845527 (this page in markdown: same URL + `.md`)
- Developer: [Joshua D. steinberg](https://appshunter.io/developer/374154837)
- Category: Medical
- Price: Free
- Rating: 2.30/5 from 15 App Store ratings · 10 written reviews indexed
- Age rating: 17+
- Requires: iOS 7.0 · 3 MB
- Languages: American English
- Released: 2015-03-23
- Data updated: 2026-08-24
- Monetization: free
- User reviews in markdown: https://appshunter.io/ios/app/ob-wheels/id969845527/reviews.md

## What is OB Wheels?

Does the world need another OB-wheel-due-date-calculator app?  You bet!  OB Wheels combines three things that clinicians need to derive all the dates necessary in pregnancy care, and no other app has this combination.   

It contains a calendar calculator to determine EDD (EDC) from LMP or from a sonogram report.  The calendar calculator also provides gestational age (EGA) as of any date for a given EDD or LMP.  Because the calculator works off the real calendar, it is accurate for leap years too.

Then for all of you who miss your cardboard OB wheel, the app contains one which you can rotate, pinch and zoom, and generally play with just like a regular cardboard wheel.  It's a little tricky to learn how to plant two fingers and rotate them rather than pinch-and-zoom to get rotation versus resizing.  But the wheel works and it is accurate, especially so because you can zoom in to be sure where the little date hash lines lie.

Finally, the app notes the most recent committee opinion scheme from ACOG on how one might reconcile due dates from LMP and sonograms to arrive at a single final EDD.  To my knowledge, the scheme is authority-based and no better or worse than other schemes, but my practice and my learners need a single clear scheme, so this app includes one for easy reference.

As an educator and clinician myself, I am grateful for feedback.  Email me via the contact email at my website.

## Key features

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

## Recent user reviews (10 of 10)

All indexed reviews: https://appshunter.io/ios/app/ob-wheels/id969845527/reviews.md

### 3/5 — App shows wrong gestation weeks and after refreshing shows correct weeks

*2024-11-17*

Need improvements in areas
Where date should be shown first and then month 

Sometimes it lags and shows wrong gestation weeks and after refreshing shows correct gestation weeks by scan

### 1/5 — Horrible

*2020-10-23*

This was very difficult to use. Deleting ASAP!

### 2/5 — Not able to enter EDD

*2020-06-25*

The app is supposed to allow the ability to enter the EDD. But it doesn’t work properly.

### 1/5 — Difficult to manipulate wheel

*2019-12-04*

Don’t bother with this one, it’s too hard to move the wheel. Plus, there is no spot for LMP on the outer wheel.

### 5/5 — Works great

*2019-08-27*

I don’t understand all the negative reviews. You put in the LMP or the ultrasound Dating and it tells you what you need to know. Simple as that. Tells you when to use U/S vs LMP also. The “wheel” is clunky and kind of pointless if you ask me. I always just use the calendar based calculator.

### 2/5 — Cumbersome

*2019-03-04*

Wheel is cumbersome and hard to use. Too much screen manipulation required to make it easy to use. Still....it’s worth the price.

### 5/5 — It IS tricky to use, but it DOES work

*2018-02-03*

So, the app has two functions. One is the Calendar Based Calculator and the other is the Traditional OB Wheel. The OB Wheel is REALLY tricky to use (the app says it so itself in the Wheel window) and does take a lot of practice to get the grip of it, but does work like any other cardboard wheel. The calculator is digital, so I don’t understand how anyone can have problem using it or find it complicated, except that don’t know how to properly use their phone and/or have little fine touch skills. 

To the developers, thanks for making this nice app and leaving it free of cost. As a suggestion, maybe if it were compatible with iPad it would be easier for more users to be able to work with the Traditional OB Wheel, as the screen of an iPhone is kinda small (even in the iPhone Plus) to maneuver it. Nevertheless, very helpful.

### 1/5 — Cumbersome

*2017-12-02, version 1.1*

Not intuitive at all.  I’d use a cardboard wheel over this, even in the dark. Two thumbs down.

### 2/5 — Difficult to use

*2017-10-03*

OB nurse for 20 years. Enjoy the online calculators rather than looking at a wheel. Neither of the applications within the app were easy to use to find the gestational age. I went looking for another.

### 1/5 — OB Wheels

*2016-03-10*

In your last update Mar 8 2016 this app never installed after many trials. Will you find solution to this problem
Thanks

## Frequently asked questions about OB Wheels

### What is OB Wheels used for?

OB Wheels is a medical app designed to help clinicians calculate important dates in pregnancy care. It includes a calendar calculator for EDD/EDC, gestational age calculation, and an interactive digital OB wheel.

### How accurate is OB Wheels?

The app's calendar calculator is accurate for leap years. The digital OB wheel allows for precise date calculations by zooming in on date hash lines.

### Does OB Wheels have ads?

No, OB Wheels does not contain advertisements. It is a free application without any ads.

### What devices support OB Wheels?

OB Wheels is supported on iPhone and iPod devices. It is designed for iOS users.

### When was OB Wheels last updated?

The latest version of OB Wheels was released on February 7, 2018. The app was initially released on March 23, 2015.

### What is the age rating for OB Wheels?

OB Wheels has an age rating of 17+. This indicates it is intended for mature users.

### How does OB Wheels help reconcile due dates?

The app includes the most recent committee opinion scheme from ACOG to help reconcile due dates derived from LMP and sonograms, providing a single final EDD for easy reference.

### What is the user rating for OB Wheels?

OB Wheels has a user rating of 2.3 stars based on 15 ratings. This suggests a mixed reception from users.

## Version history (last 3 releases)

### 1.2 — 2018-02-07

This update from Apple will improve the functionality of this app. No new features are included.

the due date calendar calculators!
- totally redesigned 
- much easier to use
- much easier to understand
- exactly what you expect from an iPhone app
- sorry I didn't improve this app earlier (but I didn't know how, still an amateur programmer)

### 1.1 — 2016-03-08

fixed truncated dates issue when iOS 9 arrived, otherwise same app

### 1.0 — 2015-03-23

No release notes.

## Apps similar to OB Wheels

| App | Rating | Price | Category |
| --- | --- | --- | --- |
| [OB Calc (cloud)](https://appshunter.io/ios/app/ob-calc-cloud/id1495610465) | 5.0 (5) | Free | Medical |
| [OB Tracker & Pregnancy Wheel](https://appshunter.io/ios/app/ob-tracker-and-pregnancy-wheel/id1454135001) | 4.8 (47) | Free | Medical |
| [OB Wheel for Pregnancy](https://appshunter.io/ios/app/ob-wheel-for-pregnancy/id6451180396) | 4.7 (39) | Free | Medical |
| [Due Date Calculator: Fertility](https://appshunter.io/ios/app/due-date-calculator-fertility/id996668841) | 4.6 (13) | Free | Medical |
| [ACOG](https://appshunter.io/ios/app/acog/id616323665) | 4.9 (6,292) | Free | Medical |
| [Ovia Cycle & Pregnancy Tracker](https://appshunter.io/ios/app/ovia-cycle-and-pregnancy-tracker/id570244389) | 4.8 (89,962) | Free | Medical |

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All apps by Joshua D. steinberg: https://appshunter.io/developer/374154837

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*Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-24.*