# Average ISA Deviation — Achieving a smooth descent > Pilot utility for calculating average ISA deviation for descent planning. (iPhone/iPad app by Juan Mauricio Padilla Villarreal.) - Source: https://appshunter.io/ios/app/average-isa-deviation/id630933637 (this page in markdown: same URL + `.md`) - Developer: [Juan Mauricio Padilla Villarreal](https://appshunter.io/developer/604279584) - Category: Navigation, Education - Price: $3.99 - Rating: 3.50/5 from 2 App Store ratings · 3 written reviews indexed - Age rating: 4+ - Requires: iOS 26.1 · 1 MB - Languages: American English - Released: 2013-04-10 - Data updated: 2026-08-01 - Monetization: paid - User reviews in markdown: https://appshunter.io/ios/app/average-isa-deviation/id630933637/reviews.md ## What is Average ISA Deviation? Average ISA Deviation is a fast and precise utility designed for pro pilots who need to calculate the average ISA temperature deviation to correctly enter the DES FORECAST in the FMC of the Boeing 737 (NG / MAX) and other aircraft. The app allows you to: • Quickly calculate the average ISA deviation • Reduce workload and potential errors during descent planning • Simplify calculations that are normally done manually • Work fully offline, ideal for cockpit use Designed by a pilot, for pilots. Legal Disclaimer This application is intended as an advisory and informational tool only. It does not replace official aeronautical charts, flight planning systems, company procedures, or regulatory guidance. ## Key features - Calculate average ISA deviation - Reduce descent planning workload - Simplify manual calculations - Offline cockpit use - Designed by a pilot ## Recent user reviews (3 of 3) All indexed reviews: https://appshunter.io/ios/app/average-isa-deviation/id630933637/reviews.md ### 2/5 — Not accurate *2025-06-08* Not very accurate. This app needs improvement. **Developer response:** Thank you for your review. I’m sorry the app didn’t meet your expectations. Average ISA Deviation is actively being improved, and feedback like yours helps make it better. If you can share more details about the calculation or result you found inaccurate, I’d be happy to investigate and improve it in an upcoming release. aviationgrade.software@gmail.com ### 5/5 — Great app... simple to use *2015-10-04* Just what I needed. A simple ISA converter that is quick and easy to use in the cruise for performance calculations. ### 4/5 — Valeu ! ! ! *2013-06-30* Gostei do app. Muito fácil. Qualquer mane vai saber usar. Só não tem 5 estrelas por que não é compatível com o iPhone. **Developer response:** There is now iPhone version! ## Frequently asked questions about Average ISA Deviation ### What is Average ISA Deviation used for? Average ISA Deviation is a utility for professional pilots to calculate the average ISA temperature deviation. This calculation is crucial for correctly entering the DES FORECAST in the FMC of aircraft like the Boeing 737 (NG/MAX). ### Does Average ISA Deviation work offline? Yes, Average ISA Deviation is designed to work fully offline. This feature makes it ideal for use in the cockpit where internet connectivity may be unreliable or unavailable. ### What is the price of Average ISA Deviation? Average ISA Deviation is a paid application, priced at $3.99. This one-time purchase provides access to its flight planning calculation features. ### What devices support Average ISA Deviation? Average ISA Deviation is supported on both iPhone and iPad devices. It is designed to be accessible on common mobile platforms used by pilots. ### How often is Average ISA Deviation updated? The latest version of Average ISA Deviation is 3.1, last updated on December 21, 2025. Updates typically focus on refining features and ensuring compatibility with evolving aviation standards. ### What is the age rating for Average ISA Deviation? Average ISA Deviation has an age rating of 4+. This indicates it is suitable for a wide range of users, including younger individuals interested in aviation. ### Is Average ISA Deviation suitable for beginners? While designed for pro pilots, the app simplifies complex calculations. However, its primary focus is on professional flight planning needs, not introductory aviation concepts. ### Does Average ISA Deviation have ads? No, Average ISA Deviation does not contain advertisements. As a paid application, it offers an ad-free experience for its users. ## Version history (last 5 releases) ### 3.1 — 2025-12-21 • Improved overall user workflow • Minor interface refinements and stability improvements ### 3.0 — 2024-10-29 More intuitive functionality, iPhone supported version. ### 2.0 — 2015-11-12 This app has been updated by Apple to display the Apple Watch app icon. Code written in Swift language. App made for iOS 9.1. ### 1.2 — 2014-04-18 The range of static air temperature is wider ### 1.1 — 2014-03-14 Made for iOS 7. Rotation Capability. ## Apps similar to Average ISA Deviation | App | Rating | Price | Category | | --- | --- | --- | --- | | [Jeppesen FliteDeck Pro](https://appshunter.io/ios/app/jeppesen-flitedeck-pro/id530174852) | 3.9 (35) | Free | Navigation | | [Jeppesen Aviator](https://appshunter.io/ios/app/jeppesen-aviator/id1135983832) | 4.9 (15) | Free | Navigation | | [AeroNOTAM](https://appshunter.io/ios/app/aeronotam/id918926129) | 3.5 (20) | Free | Navigation | ## More apps by Juan Mauricio Padilla Villarreal - [Coordinates Distance Calculator](https://appshunter.io/ios/app/coordinates-distance-calculator/id604279581) - [Descent Profile](https://appshunter.io/ios/app/descent-profile/id625841361) - [Sigmet Plotter](https://appshunter.io/ios/app/sigmet-plotter/id6737157027) All apps by Juan Mauricio Padilla Villarreal: https://appshunter.io/developer/604279584 --- *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 2026-08-01.*