ABG Expert vs ABG Pro DDx
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.
ABG Pro DDx
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Arterial Blood Gas Pro DDx. Ad supported. * Great tool for nurses, doctors and medical students * A-a Gradient Calculator * Interprets Arterial Blood Gas and Osmolar Gap including triple acid base problems. * Provides differential diagnosis of each disorder in your Arterial Blood Gas and Osmolar Gap. * Allows you to define Normal pCO2 and Bicarb range for ABG [Arterial Blood Gas] interpretation. * Corrects Anion Gap for Albumin(ie Albumin g/dL x 2.5 = normal AG) in the ABG [Arterial Blood Gas] values. * Calculates Anion Gap, Osmolar Gap, Delta Delta, Expected PCO2 and Expected Bicarb. This ABG [Arterial Blood Gas] and Osmolar Gap app has be "stress tested" against 100+ triple-acid base problems. This app has been developed by a ABIM Certified Internal Medicine Physician in the US and calculations are based on: Interpretation of arterial blood gas. Pramod Sood, Gunchan Paul, and Sandeep Puri (Indian J Crit Care Med. 2010 Apr-Jun; 14(2): 57 - 64) This application is for ABG [Arterial Blood Gas] and Osmolar Gap informational/educational purposes only. Please do not use to guide actual patient care and real life ABG interpretation. I take no responsibility for incorrect answers. Please notify me ASAP if do see incorrect answers in the ABG interpretation so that I may fix them. Please rate highly if you like the app.
Screenshots
Verdict
The clearest difference is update cadence: ABG Expert at every 5 months against ABG Pro DDx's every 20 months. ABG Expert also leads on iOS requirement (13.0 vs 15.0). On price, 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
Both are free to download. Neither carries in-app purchases, so what you see is what you pay.
ABG Expert ships an update every 5 months, ABG Pro DDx every 20 months. The most recent releases landed on October 20, 2026 and October 27, 2026 respectively.
| Parameter | ABG Expert | ABG Pro DDx |
|---|---|---|
| Price | Free | Free |
| Rating | 4.8 (9 ratings) — better | — |
| Positive reviews | 100.0% of reviews | — |
| Number of ratings | 9 — better | — |
| Update frequency | Every 5 months — better | Every 20 months |
| Ads | No | No |
| In-app purchases | No | No |
| Monetization | Free | — |
| Devices | iPhone, iPad, iPod | iPhone, iPad, iPod |
| Requires iOS | 13.0 — better | 15.0 |
| Further details — not scored | ||
| Size | 2 MB | 6 MB |
| Age rating | 12+ | 17+ |
| Developer | Brian Dale Vander Werf MD Inc | GDA Software |
In-app purchases
ABG Expert
No in-app purchases
ABG Pro DDx
No in-app purchases
Questions
Is ABG Expert free?
Is ABG Pro DDx free?
Do ABG Expert or ABG Pro DDx have ads?
Which is updated more often, ABG Expert or ABG Pro DDx?
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