Comparison

Preop Eval vs Opioid Tool

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

Head to head
About

Preop Eval

This app provides guidance for evaluating and preparing adult patients for non-cardiac surgery. It includes algorithms and resources on medication management, cardiac event timing, and preoperative testing, serving as both a reference and a teaching tool for medical professionals.

Highlights
  • Cardiac evaluation algorithm
  • Medication guidance (starting/stopping)
  • Surgery timing after cardiac events
  • Preoperative testing recommendations
  • Review for students and residents
  • Perioperative insulin management
Features
Read full description

Preop Eval organizes and presents much of the guidance that one needs in order to evaluate and prepare adult patients for non-cardiac surgery. It is based upon the guidelines on this topic from the American College of Cardiology, the European Society of Anaesthesiology, the American Society of Anesthesiologists, the Institute for Clinical Systems Improvement, the American College of Chest Physicians, and more (full references in the app). The app contains 1 algorithm and 3 resources: the cardiac evaluation algorithm, guidance on starting and stopping key medications in the perioperative period, guidance on timing of surgery after cardiac events, and guidance on preoperative testing. It also contains a review of preoperative evaluation mainly for students and residents. The app addresses such common questions as: - who needs bloodwork before surgery? - who needs an EKG or a CXR? - how do I handle patients on warfarin, clopidogrel, and DOAC's? - which patients need adjustment of perioperative insulin and diabetic meds, and how? - which active cardiac conditions preclude surgery? - how long after MI or stent should a patient wait before surgery? - are there adjustments to make on psych meds, rheumatologic meds, ACE's and ARB's? This app is written and intended for practicing physicians like internists, family physicians, and hospitalists; for resident physician trainees; and for medical students. In addition to being a reference, the algorithm is written to be a teaching tool by not just delivering an answer, but instead walking a physician through the evaluation process so that one learns that process along the way. As an educator and clinician, I am interested in feedback and I would be grateful for guidance on improving the tool.

About

Opioid Tool

This medical app provides tools for healthcare professionals rotating through specific rotations. It includes an opioid conversion calculator, a 30-day refill calculator, and a reference for opioid metabolites. A prescribing checklist is also available to aid in patient care.

Highlights
  • Opioid conversion calculator
  • 30-day refill calculator
  • Opioid metabolite reference
  • Prescribing checklist
Features
Read full description

An app for fellows and residents rotating through Dr. Bernstein's rotation. It contains an opioid conversion calculator, 30 day refill calculator, opioid metabolite reference, and prescribing checklist.

Screenshots

Preop Eval4 screens
Opioid Tool1 screens

Verdict

The call

The clearest difference is rating: Preop Eval at 5.0 against Opioid Tool's 3.6. Preop Eval also leads on review sentiment (67% vs 40%). Opioid Tool's advantage is update cadence (every 5 days vs every 6 months) and ratings volume (8 vs 2). On price, ads, in-app purchases and monetization model 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

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

ReceptionRating · Positive reviews · Number of ratings

Preop Eval holds the better App Store score, 5.0 against 3.6. Both are backed by a comparable volume of ratings — 2 and 8 respectively. Written reviews point the same way: 67% of Preop Eval's written reviews are positive against 40% of Opioid Tool's.

UpkeepUpdate frequency

Preop Eval ships an update every 6 months, Opioid Tool every 5 days. Both last shipped on September 10, 2026.

Scorecard5 real differences · 5 level
Preop Eval versus Opioid Tool: the parameters behind the verdict, then further details
ParameterPreop EvalOpioid Tool
PriceFreeFree
Rating5.0 (2 ratings) — better3.6 (8 ratings)
Positive reviews66.7% of reviews — better40.0% of reviews
Number of ratings28 — better
Update frequencyEvery 6 monthsEvery 5 days — better
AdsNoNo
In-app purchasesNoNo
MonetizationFreeFree
DevicesiPhone, iPodiPhone, iPod
Requires iOS16.67.0 — better
Further details — not scored
Size15 MB1 MB
Age rating17+4+
DeveloperUnited Health Services, Inc.aaron sobol

Customer experience

Preop Eval

All ratings2 ratings
Positive100.0%
Neutral0.0%
Negative0.0%
Written reviews12 reviews
Positive66.7%
Neutral8.3%
Negative25.0%

Opioid Tool

All ratings8 ratings
Positive75.0%
Neutral0.0%
Negative25.0%
Written reviews5 reviews
Positive40.0%
Neutral0.0%
Negative60.0%

In-app purchases

None

Preop Eval

No in-app purchases

None

Opioid Tool

No in-app purchases

Questions

Is Preop Eval free?
Preop Eval is free to download, with no in-app purchases.
Is Opioid Tool free?
Opioid Tool is free to download, with no in-app purchases.
Which has better reviews, Preop Eval or Opioid Tool?
Preop Eval is rated higher. Preop Eval averages 5.0 out of 5 from 2 ratings, while Opioid Tool averages 3.6 from 8 ratings.
Do Preop Eval or Opioid Tool have ads?
Neither Preop Eval nor Opioid Tool shows ads.
Which is updated more often, Preop Eval or Opioid Tool?
Preop Eval ships an update every 6 months, and Opioid Tool every 5 days. Most recently, Preop Eval was updated on September 10, 2026 and Opioid Tool on September 10, 2026.

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