# Acid Plus - The ABG Calculator — user reviews > 34 indexed App Store user reviews of Acid Plus by Free Radical Software, rated 4.90/5 from 71 ratings. - Source: https://appshunter.io/ios/app/acid-plus-the-abg-calculator/id300521236/reviews - App overview in markdown: https://appshunter.io/ios/app/acid-plus-the-abg-calculator/id300521236.md - Rating breakdown: 5★ 67 · 4★ 3 · 3★ 1 · 2★ 0 · 1★ 0 ## Newest reviews (11 of 34) ### 3/5 — Need the update *2017-11-06* It was a 5 star but not able to use with new IOS so rating is zero. Three is until update so I can use again and bring rating back to five. Please update **Developer response:** We're glad you liked using Acid Plus, but we're sorry it was unavailable to you. We're back now with the new and improved version 3, which should run your great on your iPhone or iPad. If you like the new version, please consider updating your review. And since we made you wait, please email us at support@freeradicalsoft.com and we'll send you a code for year-long free subscription. ### 3/5 — たしかに便利だが。。。 *2010-04-21* 直感的でかなり分かりやすい。 デザインもなかなか秀逸。 が、、、頭で解釈しなくなってしまうのも、いざという時困る気がする。 そもそも考え方さえ理解していれば入力するより先に解釈できてしまう。結局、実際の臨床(特に救急)では、あとからの答え合わせ程度にしか利用用途がない気がしないでもない。。。 あとは混合型障害のときには時に判定が微妙なので注意が必要。 ### 3/5 — basic *2010-04-14, version 0* Per chi, come me, ha sempre avuto dei problemi nel valutare i valori di EGA direi che è uno strumento interessante. ### 3/5 — acid plus *2010-04-04, version 0* non supporta tutte le possibili combinazioni interpretative dell'ega ### 4/5 — WHERE IS BASE EXCESS/DEFICIT *2010-03-08, version 0* WHY IS BASE EXCESS/DEFICIT NOT A PARAMETER IN YOUR LIST FOR ABG ANALYSIS? ### 4/5 — グラフが見やすい *2010-03-04* 救急でさっとみれますね！ ### 3/5 — Getting Better *2009-09-21* There have been several more updates since my last review and I think the program has come a long way. Improvents could include showing the Henderson hasselbach results so you know you're working with good numbers to start. I also run into quite a few triple disorders and seeing all the calculated numbers would be useful instead of having to manually calculate it every time. Anyway, this program should still be used with caution, but it can at least point you in the right direction now. ### 3/5 — An improvement that could be made *2009-07-23* Could factor in anion gap adjustment that depend on albumin levels. ### 3/5 — Dr *2009-06-28* Good. Needs to be an option to use H+ ### 4/5 — カチカチと *2009-02-15* これはシンプルだし、いいですよ。 ### 5/5 — Good for students *2009-01-26* I will be recommending this app to my nursing students. It's a great way to see how small changes lead to large problems. Excellent use of the iPhone interface. ## Most critical reviews (10 lowest-rated) ### 1/5 — Needs update *2018-04-17* It was great but can’t use it anymore **Developer response:** Glad you liked using Acid Plus, but sorry it was unavailable to you. We're back now with the new and improved version 3, which should run your great on your iPhone or iPad. If you like the new version, please consider updating your review. And since we made you wait, please email us at support@freeradicalsoft.com and we'll send you a code for year-long free subscription. ### 1/5 — I want my money back!!! *2018-02-11* It doesn't work for IOS 10!!! Shame on you!! Please fix this bug **Developer response:** Glad you liked using Acid Plus, but sorry it was unavailable to you. We're back now with the new and improved version 3, which should run your great on your iPhone or iPad. If you like the new version, please consider updating your review. And since we made you wait, please email us at support@freeradicalsoft.com and we'll send you a code for year-long free subscription. ### 1/5 — Doesn’t work *2017-11-14* Doesn’t work with new iOS update **Developer response:** Glad you liked using Acid Plus, but we're sorry it was unavailable to you. We're back now with the new and improved version 3, which should run your great on your iPhone or iPad. If you like the new version, please consider updating your review. And since we made you wait, please email us at support@freeradicalsoft.com and we'll send you a code for year-long free subscription. ### 1/5 — Outdated *2017-10-31* How good is it if it does not work with iOS 11? Update soon to go back to 5 stars. **Developer response:** We're very glad you liked using Acid Plus, and we're sorry it was unavailable to you for so long! We're back now with the new and improved version 3, which should run your great on your iPhone or iPad. If you like the new version, please consider updating your review. And since we made you wait, please email us at support@freeradicalsoft.com and we'll send you a code for year-long free subscription. ### 1/5 — Does not work anymore... *2013-12-17* It must be with the last software uptade on Iphone 5. When I open it, frozen screen and can't do anything... Please update App to fix this bug!! ### 1/5 — acid plus The ABG Calculator *2010-06-14* It takes me to it's web site to sell me other products. I don't like that!.The free ABG App is better. What a waist of $ 3.99 !!! ### 1/5 — practitoner *2010-03-09* Waist of time. It can not handle mixed acid base problems like an aspirin overdose. It will give an error message "these numbers violate the HH equation." I guess my patients failed math. ### 1/5 — fatal flaw *2009-01-20* Literally...using this program could result in a fatality as the information is inaccurate. A new update should be put out soon, but until then this program is worthless ### 2/5 — when updated to iOS11？ *2017-11-13* can't wait **Developer response:** Glad you liked using Acid Plus, but sorry it was unavailable to you. We're back now with the new and improved version 3, which should run your great on your iPhone or iPad. If you like the new version, please consider updating your review. And since we made you wait, please email us at support@freeradicalsoft.com and we'll send you a code for year-long free subscription. ### 2/5 — Stopped working! *2013-11-26* This is a great little app, however, it stopped working (frozen) on my iPhone5s! Please fix. ## Most praised reviews (10 highest-rated) ### 5/5 — Love this ABG app *2021-07-04* The perfect app for the wards. The picker for choosing values is great. ### 5/5 — So great to see this app return! *2021-07-04* I’ve been missing this for a while but all the extra details available and being able to set the graph manually are really useful. Great update, thanks! ### 5/5 — So useful *2021-07-02* Not only is it easy to use but there’s just so much detailed info available. Really helpful to be able to see how all the results are derived. ### 5/5 — Great app *2018-10-22* Please update for new IOS versions!!!!! **Developer response:** Acid Plus version 3 is now available and should work with your iPhone or iPad. To welcome you back, please email us at support@freeradicalsoft.com and we'll send you a code for year-long free subscription. ### 5/5 — Good *2018-10-09* Update ur software as I love this program Hurry up ### 5/5 — Please update *2017-10-17* I have loved using this app and would really like to keep using it. Can you please update to allow me to keep using it. ### 5/5 — Don't stay to much on this app *2009-12-08* You might be addicted ### 5/5 — Fast, accurate, and useful *2009-09-13* I'm a medical student who is going through the core medicine rotatation. I have used this app several times to analyze ABG's and it does the job quite well. You can recall previous entries with the refresh button. The graph mode that shows you were you are on the blood gas spectrum is also very helpful. A venous blood gas analysis mode (limited as it is) would also be helpful. It would also be helpful if it was possible to more explicity save prior ABG analyses. I have compared the results from Acid Plus with the results from the Mediquations Acid-Base compensation. The two are consistent but at times when the ABG are somewhat off (due to analyzer issues, etc.) or otherwise ambiguous, Mediquations provides alternative interpretations, which Acid Plus does not. However, Acid Plus has been reasonable and presented the most likely interpretation which has been consistent with clinical observations in cases that I have checked. One area of possible inaccuracy could occur in cases where the albumin is very low. From Rennke and Denker (2007), in hypoalbuminemia, the normal anion gap value must be adjusted downward. "The approximate correction factor is a reduction in the anion gap of 1.5 mEq/L for every 1.0-g/dL reduction {from 4.0 to 4.5} in the plasma albumin concentration ...." Thus, low albumin can change the interpretation of anion gap. This application does not consider this. ### 5/5 — great for ICU *2009-07-31* As a resident, I can't emphasize enough on how useful the app is. I used it extensively in the critical care setting and it works great!!!!! Very accurate and extremely easy to use. You should definitely get it. ### 5/5 — Marc D. Davis, PA-C *2009-07-23* Acid Plus continues to be the leading ABG Calculator for the iPhone-iPod touch. I have been a PA-C for 11yrs practicing Nephrology and interpret ABGs daily. This App is spot on, excellent work guys. I strongly recommend this App without reservation for all. --- *Data collected daily from the US App Store and indexed by [AppsHunter](https://appshunter.io/). User reviews are verbatim App Store reviews. Ratings, prices and chart positions refresh continuously; this snapshot is from 2026-08-27.*