# Perfect OB Wheel vs EFM

The clearest difference is review sentiment: Perfect OB Wheel at 83% against EFM's 0%. Perfect OB Wheel also leads on rating (4.9 vs 1.0) and update cadence (weekly vs every 12 months). EFM's advantage is price (Free vs $1.99) and in-app purchases (none vs 1). On ads and device support there is nothing between them.

EFM is free to download; Perfect OB Wheel costs $1.99 up front. Perfect OB Wheel sells 1 one-off in-app purchase. EFM asks for nothing beyond the download.

Perfect OB Wheel holds the better App Store score, 4.9 against 1.0. That said, the two scores are not equally well evidenced: Perfect OB Wheel has 3.6K ratings behind it against 3, so its average is the more settled of the two. Written reviews point the same way: 83% of Perfect OB Wheel's written reviews are positive against 0% of EFM's.

Perfect OB Wheel ships an update weekly, EFM every 12 months. The most recent releases landed on November 6, 2026 and November 1, 2026 respectively.

## The numbers

| Metric | Perfect OB Wheel | EFM |
| --- | --- | --- |
| Price | $1.99 | **Free** |
| Rating | **[4.9 (3.6K ratings)](https://appshunter.io/ios/app/perfect-ob-wheel/id293656711/reviews)** | [1.0 (3 ratings)](https://appshunter.io/ios/app/efm/id834501088/reviews) |
| Number of ratings | **3.6K** | 3 |
| Positive reviews | **83.0% of reviews** | 0.0% of reviews |
| In-app purchases | Yes | **No** |
| Ads | No | No |
| Update frequency | **Weekly** | Every 12 months |
| Monetization | Free with in-app purchases | **Free** |
| Best chart rank | **#21** | — |
| Size | 14 MB | 5 MB |
| Requires iOS | 13.0 | **7.0** |
| Devices | **iPhone, iPad, iPod** | iPhone, iPod |
| Age rating | 17+ | 12+ |
| Developer | [Evan Schoenberg](https://appshunter.io/developer/289039917) | [Augusta University](https://appshunter.io/developer/319778530) |

## What reviewers say

### Perfect OB Wheel

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

**Currently charting:** #21 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


### EFM

[App page](https://appshunter.io/ios/app/efm/id834501088)

This is an instructional application for learning electronic fetal monitoring using a recognized algorithm and nomenclature. It is designed for educational purposes and is not a substitute for professional clinical judgment. Future updates aim to include data saving and demographic features.

**Highlights:** Electronic fetal monitoring instruction, NCHHD algorithm and nomenclature, Instructional purposes, Collaborative project inquiries, Future data saving capability

**Features:** macOS Compatibility

**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 EFM free?

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

### Which has better reviews, Perfect OB Wheel or EFM?

Perfect OB Wheel is rated higher. Perfect OB Wheel averages 4.9 out of 5 from 3.6K ratings, while EFM averages 1.0 from 3 ratings.

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

Neither Perfect OB Wheel nor EFM shows ads.

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

Perfect OB Wheel ships an update weekly, and EFM every 12 months. Most recently, Perfect OB Wheel was updated on November 6, 2026 and EFM on November 1, 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.*