ABG Expert vs Critical ABG
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
ABG Expert
This medical tool provides accurate and flexible acid-base analysis for healthcare professionals. It offers detailed explanations, customizable ranges, and advanced features like anion gap correction and A-a gradient adjustments for various patient conditions and locations.
- Validated accuracy with real-world testing
- Plausibility checks for physiologically impossible data
- Automatic anion gap correction with albumin
- Detailed explanations with equations
- Separate or combined analysis of ABG, anion gap, A-a gradient
- Customizable normal ranges for anion gap and delta gap
- Age and barometric pressure adjustments for A-a gradient
- Support for SI and non-SI units
- Color-coded results and differential diagnoses
- Adjustments for chronic respiratory conditions
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ABG Expert™ is simply the best acid-base analysis tool with features available in no other app. Designed and tested by practicing physicians, ABG Expert is trusted by medical professionals for unparalleled accuracy, flexibility, and power while remaining completely intuitive to use. Whether you are a physician, nurse, respiratory therapist, paramedic, or student, ABG Expert is your ideal acid base analysis app. Accuracy- • ABG Expert has been validated using extensive testing under real-world conditions. • No need to worry about entering physiologically impossible data by mistake. Data is checked for plausibility and for internal consistency using the Henderson-Hasselbalch equation. • An accurate analysis depends on an accurate anion gap. ABG Expert has you covered with automatic correction of the anion gap when albumin is provided. • Never again wonder about how a result was obtained. Detailed explanations include easy-to-understand equations so you can be sure the calculations are correct. Flexibility- • Need the arterial blood gas analysis, but not the anion gap or A-a gradient? No problem. ABG Expert can analyze the data for all three results separately or together. • Set the normal anion gap range based on the normal range at your institution. Or, use your patient’s own baseline anion gap to maximize your sensitivity to detect disorders. • Caring for an 80-year-old patient in Denver? Provide age and barometric pressure, and ABG Expert automatically adjusts interpretation of the A-a gradient. • Need more specificity? Adjust the normal delta gap range based on the literature you follow in your practice. • ABG Expert works as well in Bangkok as it does in Boston with full support for SI and non-SI units. Power- • Color-coded results allow for rapid analysis in critical situations. One additional click gives you a detailed differential diagnosis and additional recommendations. • Concerned about a new problem in your patient with advanced COPD? ABG Expert can adjust its calculations for chronic respiratory conditions so you can detect additional disorders that are missed by other apps. • Detailed explanations of disorders integrate ABG, anion gap, and A-a gradient results providing individualized answers like no textbook can. • Refine your differential diagnosis even further with the included osmolal gap and urine anion gap calculators. • ABG Expert combines beauty and brains with optimization for iOS devices running iOS 13 and later. Disclaimer: Brian Dale Vander Werf MD Inc. has made every effort to ensure the accuracy of the information included in this product. However, the authors, developers, and Brian Dale Vander Werf MD Inc. are not responsible for errors or omissions or for any consequences from the use of this product and make no warranty, expressed or implied, with respect to the currency, completeness, or accuracy of the contents of this product. This product has been designed as a supplemental source of information for medical professionals. This product is not a substitute for clinical judgment, and the use of the information produced by this product in a particular situation remains the responsibility of the medical professional. Privacy Policy: This product does not collect, store, or transmit individually identifiable health information. References: NEJM. 2014; 371: 1434. Medicine. 1980; 59(3): 161. Kidney International. 2009; 76: 1239. Emerg Med. 1990; 19: 1310. Clin J Am Soc Nephrol. 2007; 2: 162. Nat Rev Nephrol. 2010; 6: 274. Anaesthesia. 2008; 63: 294. Clin J Am Soc Nephrol. 2012; 7: 671. The ICU Book. 3rd ed. Lippincott Williams & Wilkins; 2007.
Critical ABG
This medical app provides a comprehensive analysis of acid-base disorders with a step-by-step approach to understanding them. It includes common causes, differential treatment options, and built-in compensation mechanisms. An optimization calculator for ventilator settings is also available.
- Acid-base disorder analysis
- Step-by-step understanding
- Common causes and treatments
- Compensation mechanisms
- Ventilation optimization calculator
- Differential diagnosis
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Critical ABG, from the creators of Critical-Medical Guide, is the first ABG app that is not only visually appealing but also provides a full analysis of acid-base disorders. We're all afraid of acid-base imbalances. Critical ABG will not only inform clinicians whether acid-base problems are present, but will also take you through a step-by-step approach to cognitively understanding the disorder, as well as common causes and differential treatment options based on the current literature. Critical ABG covers some of the most up-to-date differentials and treatments, as well as built-in compensation mechanisms, such as expected bicarbonate, pC02, Winter's formula, and more, - which everyone dreads having to memorize. Not only will the user learn about common disorders, but there's also a ventilation optimization calculator for those that need to adjust ventilator settings. This app is not only suited for physicians, respiratory therapists, nurses, and PA's but also medical, nursing, PA, and paramedic students who wish to sharpen their acid-base interpretation skills. Remember always to treat the patient - not the numbers and to correlate clinically. Get Critical ABG now and enjoy the ease of interpretation. Critical ABG is based on common equations in the medical realm. The information included is solely for educational purposes and doesn't constitute medical advice. Therefore, always consult a physician before any diagnosis or treatment.
Screenshots
Verdict
The clearest difference is review sentiment: ABG Expert at 100% against Critical ABG's 50%. ABG Expert also leads on price (Free vs $3.99) and rating (4.8 vs 4.0). Critical ABG's advantage is chart position (#171 vs unranked). On ratings volume, 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
ABG Expert is free to download; Critical ABG costs $3.99 up front. Neither carries in-app purchases, so what you see is what you pay.
ABG Expert holds the better App Store score, 4.8 against 4.0. Both are backed by a comparable volume of ratings — 9 and 4 respectively. Written reviews point the same way: 100% of ABG Expert's written reviews are positive against 50% of Critical ABG's.
ABG Expert ships an update every 5 months, Critical ABG every 42 months. The most recent releases landed on November 1, 2026 and November 2, 2026 respectively.
| Parameter | ABG Expert | Critical ABG |
|---|---|---|
| Price | Free — better | $3.99 |
| Rating | 4.8 (9 ratings) — better | 4.0 (4 ratings) |
| Positive reviews | 100.0% of reviews — better | 50.0% of reviews |
| Number of ratings | 9 — better | 4 |
| Update frequency | Every 5 months — better | Every 42 months |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free — better | Paid |
| Best chart rank | — | #171 — better |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Requires iOS | 13.0 — better | 15.2 |
| Further details — not scored | ||
| Size | 2 MB | 3 MB |
| Age rating | 12+ | 17+ |
| Developer | Brian Dale Vander Werf MD Inc | The Barringer Group, LLC |
Customer experience
ABG Expert
Critical ABG
In-app purchases
ABG Expert
No in-app purchases
Critical ABG
No in-app purchases
Questions
Is ABG Expert free?
Is Critical ABG free?
Which has better reviews, ABG Expert or Critical ABG?
Do ABG Expert or Critical ABG have ads?
Which is updated more often, ABG Expert or Critical ABG?
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