Comparison

Perfect OB Tracker vs ONI DIDI +

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Perfect OB Tracker

This app provides a comprehensive pregnancy wheel and tracker for medical professionals. It allows for managing multiple patients, calculating due dates, tracking gestational age, and even monitoring postpartum information. The tool offers quick calculations and detailed fetal growth estimates.

Highlights
  • Patient management
  • Due date calculation
  • Gestational age tracking
  • Postpartum tracking
  • Quick calculator
  • Fetal growth estimates
  • HIPAA compliant passcode lock
Features
Currently charting
Read full description

Simple, fast, yet more thorough than any other pregnancy wheel available for the iPhone, Perfect OB Tracker is better than just a replacement for your trusty paper wheel. • Keep track of any number of pregnant patients with at-a-glance due date and gestational age • Synchronize to all your iOS devices via iCloud (optional) • Sort by name or due date • Search by name or medical record number • Keep notes on each patient • Track postpartum, as well, noting delivery date, gender, and name • Quick Calculator lets you use the OB wheel without having to enter patient data for one-off calculations 1) Start with one of: • Last menstrual period (LMP) • Conception date • Estimated date of confinement/delivery (EDC) • Ultrasound dating: Number of weeks and days gestation as of a given date ("X Weeks"). Enter dates quickly with the intelligent keypad (which knows when you're done typing the month, for example, and automatically moves to the day) or with the spinning date wheel. 2) Get thorough results: All the information you would expect from a classic wheel, plus more: • Estimated Due Date • LMP Date • Conception Date • 1st Trimester End Date • 2nd Trimester End Date • Gestational Age • Conceptional Age • Expected Fetal Length based on standard fetal growth curves • Expected Fetal Weight based on standard fetal growth curves ("How much does my baby weigh, doctor?") Results are relative to 'today' by default; this can be quickly changed to reflect any date by tapping the 'today' button and selecting a new date. 3) Accurate results: Perfect OB Wheel provides exact dates and accounts for all calendar variance, including leap years. 4) Secure: HIPAA complaint passcode locking keeps your patient information safe

About

ONI DIDI +

Features
Read full description

ONI is an integrated platform that connects couples and obstetricians/gynecologists (Ob-Gyns), focusing on the first 1,000 days of life. ONI DIDI + is an AI-assisted platform that helps Ob-Gyns streamline appointments and electronic medical records (EMR). It enables doctors to manage patient consultations using voice commands, assist in prescription management, recommend pregnancy-related tests, view reports, and record vital health data. The app is designed to be simple and easy to use. Disclaimer: ONI DIDI + is intended for informational and assistance purposes only and does not provide medical advice, diagnosis, or treatment. Always consult a qualified healthcare professional for any medical concerns or decisions. AI-powered features are designed to assist healthcare professionals and should not be considered medical advice.

Screenshots

Perfect OB Tracker4 screens
ONI DIDI +4 screens

Verdict

The call

The clearest difference is price: ONI DIDI + at Free against Perfect OB Tracker's $6.99. Perfect OB Tracker's advantage is chart position (#131 vs unranked) and iOS requirement (13.0 vs 15.6). On update cadence, ads, in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

ONI DIDI + is free to download; Perfect OB Tracker costs $6.99 up front. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Perfect OB Tracker ships an update every 2 weeks, ONI DIDI + fortnightly. The most recent releases landed on October 14, 2026 and October 8, 2026 respectively.

Scorecard3 real differences · 8 level
Perfect OB Tracker versus ONI DIDI +: the parameters behind the verdict, then further details
ParameterPerfect OB TrackerONI DIDI +
Price$6.99Free — better
Rating4.9 (408 ratings) — better—
Positive reviews74.1% of reviews—
Number of ratings408 — better—
Update frequencyEvery 2 weeksFortnightly — better
AdsNoNo
In-app purchasesNoNo
MonetizationPaid—
Best chart rank#131 — better—
DevicesiPhone, iPad, iPod — betteriPhone, iPod
Requires iOS13.0 — better15.6
Further details — not scored
Size12 MB33 MB
Age rating17+4+
DeveloperEvan SchoenbergOniCares Education Pvt Ltd

Bugs and requests

Perfect OB Tracker

Reported bugs

9 issues
  • App just stopped working properly
  • App stopped working out of nowhere
  • Lost all records when changing phones
  • Syncing data to iPad is not working
  • Dates change erratically when toggling between patients
Show 4 more
  • App doesn't open on iOS 6
  • Update caused app to not open and lost all info
  • Won't sync to new iPhone
  • iCloud option not working better

Requested features

48 requests
  • Ability to share data with assistants
  • More options for writing notes
  • More customizable for practice
  • Way to share data with assistants
  • Export list to Word or Excel
Show 43 more
  • Ability to copy and paste data
  • List of patients due each month through the year
  • Android version of the app
  • Ability to sync with other users
  • Enter phone number and dial directly from the app
  • Add delivery date to prevent patients appearing as post dates
  • Ability to keep track of delivered patients for reporting
  • Identify primary vs. secondary midwife clients
  • Amend name, MRN, and photo after setup
  • Ability to sync up with other people
  • Link to phone's calendar for appointments
  • Option to mark patients as delivered and archive them
  • Add alarm for certain dates
  • Postpartum tracking
  • Enter phone number and relate to phone agenda
  • Ability to keep patient name after delivery for a few months
  • Delivery date and postpartum date counter
  • Sync with iPad through the cloud
  • More functionality for gestational age and patient data (infections, blood type)
  • iCloud communication between devices
  • More complicated password system
  • Add delivery date and track time since birth for postnatal care
  • Option to enter phone number and dial directly
  • Add delivery date so patients don't appear as post dates
  • Ability to keep track of delivered patients for reporting
  • More options for notes and customization
  • Identify primary vs. secondary midwife clients
  • Amend name, MRN, and photo after setup
  • Sync with other users
  • Android version
  • Export data
  • More detailed patient information fields (parity, delivery route, age, comorbidity, health plan)
  • Add alarm for specific dates
  • Postpartum tracking
  • Link appointments to phone calendar
  • Option to delete delivered patients
  • More complicated password system
  • Sync with iPad via iCloud
  • Ability to keep patient name after delivery for follow-up
  • Delivery date and postpartum date counter
  • Sync with iPad through the cloud
  • More detailed patient data fields
  • iCloud sync between devices

ONI DIDI +

Not enough reviews yet to summarise bugs or requests.

In-app purchases

None

Perfect OB Tracker

No in-app purchases

None

ONI DIDI +

No in-app purchases

Questions

Is Perfect OB Tracker free?
Perfect OB Tracker costs $6.99, with no in-app purchases.
Is ONI DIDI + free?
ONI DIDI + is free to download, with no in-app purchases.
Do Perfect OB Tracker or ONI DIDI + have ads?
Neither Perfect OB Tracker nor ONI DIDI + shows ads.
Which is updated more often, Perfect OB Tracker or ONI DIDI +?
Perfect OB Tracker ships an update every 2 weeks, and ONI DIDI + fortnightly. Most recently, Perfect OB Tracker was updated on October 14, 2026 and ONI DIDI + on October 8, 2026.

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