# Perfect OB Wheel vs ObCalc

The clearest difference is in-app purchases: ObCalc at none against Perfect OB Wheel's 1. Perfect OB Wheel's advantage is price ($1.99 vs $6.99) and update cadence (weekly vs every 5 weeks). On ads and device support there is nothing between them.

Perfect OB Wheel costs $1.99 and ObCalc $6.99 up front. Perfect OB Wheel sells 1 one-off in-app purchase. ObCalc asks for nothing beyond the download.

Perfect OB Wheel ships an update weekly, ObCalc every 5 weeks. The most recent releases landed on November 10, 2026 and November 11, 2026 respectively.

## The numbers

| Metric | Perfect OB Wheel | ObCalc |
| --- | --- | --- |
| Price | **$1.99** | $6.99 |
| Rating | **[4.9 (3.6K ratings)](https://appshunter.io/ios/app/perfect-ob-wheel/id293656711/reviews)** | — |
| Number of ratings | **3.6K** | — |
| Positive reviews | 83.0% of reviews | — |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Weekly** | Every 5 weeks |
| Monetization | Free with in-app purchases | — |
| Best chart rank | **#57** | — |
| Size | 14 MB | 3 MB |
| Requires iOS | **13.0** | 26.0 |
| Devices | **iPhone, iPad, iPod** | iPhone, iPad |
| Age rating | 17+ | 17+ |
| Developer | [Evan Schoenberg](https://appshunter.io/developer/289039917) | [Code Nine Labs LLC](https://appshunter.io/developer/983427275) |

## What reviewers say

### Perfect OB Wheel

[App page](https://appshunter.io/ios/app/perfect-ob-wheel/id293656711)

**Currently charting:** #57 Top Paid · Medical (US App Store)

This app is a comprehensive obstetrics calculator that provides detailed pregnancy information. It offers flexible input options and displays thorough results including estimated due dates, gestational ages, and fetal growth estimates.

**Highlights:** Flexible input (LMP, conception, EDC, ultrasound), Fast data entry options, Detailed pregnancy results, Accurate date calculations, Persistence of last used data, Optional pregnancy tracking upgrade

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

**In-app purchases (1)**

| Purchase | Price | Billing |
| --- | --- | --- |
| Perfect OB Tracker | $4.99 | one-time |

**What reviewers like**

- 🚀 Extremely helpful
- 🚀 Couldn't do my job without it
- 🚀 Perfect wheel is well-named
- 🚀 I love this app!
- 🚀 Great app!!

**What reviewers complain about**

- 🐛 rip off to force you to pay more
- 🐛 App stopped opening
- 🐛 Stopped working after update 45
- 🐛 Crashing!!
- 🐛 Latest update

**Reported bugs**

- App crashes after update
- Delivered today button not working after upgrade
- Dates keep changing when entering info

**Requested features**

- Date-adjustment for women who have a five week menstrual cycle
- More fields for infant info, apgars and weight
- Ability to adjust cycle length
- Ability to type in a gestation and get a date or type in a date and get a gestation
- Calculate GA on a specific date


### ObCalc

[App page](https://appshunter.io/ios/app/obcalc/id983427276)

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

**In-app purchases:** none


## Frequently asked questions

### Is Perfect OB Wheel free?

Perfect OB Wheel costs $1.99, and also offers in-app purchases.

### Is ObCalc free?

ObCalc costs $6.99, with no in-app purchases.

### Do Perfect OB Wheel or ObCalc have ads?

Neither Perfect OB Wheel nor ObCalc shows ads.

### Which is updated more often, Perfect OB Wheel or ObCalc?

Perfect OB Wheel ships an update weekly, and ObCalc every 5 weeks. Most recently, Perfect OB Wheel was updated on November 10, 2026 and ObCalc on November 11, 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.*