# iCAS > Mobile computer algebra system for advanced mathematical computations and plotting. (iPhone/iPad app by Antonio Lagana.) - Source: https://appshunter.io/ios/app/icas/id394637176 (this page in markdown: same URL + `.md`) - Developer: [Antonio Lagana](https://appshunter.io/developer/289068868) - Category: Productivity, Utilities - Price: $14.99 - Rating: 4.83/5 from 6 App Store ratings · 8 written reviews indexed - Age rating: 4+ - Requires: iOS 9.0 · 21 MB - Languages: English - Released: 2010-12-16 - Data updated: 2026-06-10 - Monetization: paid - User reviews in markdown: https://appshunter.io/ios/app/icas/id394637176/reviews.md ## What is iCAS? If you use REDUCE, you can now perform your computations anywhere on your iOS device of choice. iCAS is a complete and native implementation of REDUCE with all of its major packages, including the gnuplot package. If you have an iPhone 4/iPad or later devices, you can even use the iCAS screen mirroring feature to share your results/plots with your colleagues, walk a class through computations, etc. If you're not familiar with REDUCE, it is an extremely powerful and flexible computer algebra system with a track record spanning over 40 years of use in the engineering, computer science, and physics research community. Simply put, iCAS is like having Mathematica or the computational engine of Wolfram Alpha in your pocket but, best of all, it runs natively on your iOS device so no internet connection is required. iCAS is fully programmable and provides the ability to reuse previous results in computations. iCAS is all about getting computations done. Its simple, clean, and uncluttered interface is quick and nimble and stays out of your way and fancy graphics are used only where it matters, for fancy output and plots. The CAS engine in iCAS has been in use for decades on desktop machines and is identical to the one used in the i41CX+ iOS app. The following are just some of the i41CX+ user comments praising the powerful CAS engine. "Try this: x1 := sqrt(h^2 + p1^2); x2 := sqrt((h/2)^2 + (p-p1)^2); x3 := x1 + x2; dx := df(x3,p1); solve(dx,p1); This great calculator gives the correct answer 2p/3 instantly. Not even SpaceTime nor any other portable CAS can handle this." "I have this equation that I have tried to reduce in CalcCenter to little success as well as TInspire and others. The equation is error = ((((-r1*(1+k1))/(r2*(1+k2)))+((r1)/(r2)))/(((r1)/(r2)))). Can the i41CX+ [CAS] solve this?" The CAS engine simplified the expression to (-k1 + k2)/(k2 + 1) and this user became yet another satisfied user of this powerful CAS engine. APP FEATURES: • Three modes of operation: CAS, Plotter, and Text Editor • Interactive and batch mode execution • User configurable macro keyboard • Numerical keyboard for quick arithmetic calculations • Rich set of user configuration options (e.g. enabled keyboards, keyboard configuration, automatically show plots or fancy output, etc.) • Configurable font style, font size, foreground and background colors • Support for all device orientations • External screen mirroring support (iPhone 4 and iPad) • Import/export via email and iTunes file sharing • AirPrint support • Fancy output rendering engine can also be used for basic rendering of LaTeX files CAS FEATURES • Expansion and ordering of polynomials and rational functions • Substitutions and pattern matching in a wide variety of forms • Automatic and user controlled simplification of expressions • Calculations with symbolic matrices • Arbitrary precision integer and real arithmetic • Facilities for defining new functions • Analytic differentiation and integration • Factorization of polynomials • Solving a variety of algebraic equations • Facilities for the output of expressions in a variety of formats • 2D and 3D plotting either using the REDUCE gnuplot package or via direct gnuplot commands • And Much More ## Key features - Computer algebra system (CAS) - Plot generation - Text editor - Interactive and batch execution - Screen mirroring - Import/export via email and iTunes - LaTeX rendering ## Recent user reviews (8 of 8) All indexed reviews: https://appshunter.io/ios/app/icas/id394637176/reviews.md ### 5/5 — Reduce is great as solving, not a great UI. *2020-10-21, version 2.4.5* It took me a while to find reduce on my own. Also a good book, algorithms for computer algebra. Reduce definitely needs a more user friendly AI. It does solves problems other CAS systems seem to fail at. It would be great to one day get a better UI version available for desktops. A note of something simple to add...an output window, and a shift enter to run line and a run all. Confusing how to get something to evaluate. This small addition would make it convenient, part of the problem I have with reduce the free desktop version is that the user interface is inconvenient to work with. That being said, I will say again, several times reduce solves things that others seem to fail at, glad someone has started on moving it forward. Five stars for the start, haven’t used that much, but if it’s the reduce core it is capable of solving problems. Thanks. ### 5/5 — Deserves far more than 5 stars *2014-11-01, version 2.2.2* This product is a real prize in all ways for mathematicians, scientists, and engineers. It is complete in all ways. It does both numeric and symbolic calculations involving algebra, statistics, calculus, linear algebra, etc. it has arbitrary precision, beautifully handles 2 and 3 dimensional graphing, and is comparable with Mathematica on all levels, but is far less expensive. Of all the apps I have ever downloaded it has to be among the very best! I can't say enough good about it! Thumbs up!!! Also, by the way, it is not dependent on internet connection in order to function. A real prize! ### 2/5 — Limited usefulness *2014-06-09, version 2.1.3* If you've used Reduce on the desktop this will let you keep working. If you are new to Reduce this app is too limiting. You can pull up instructions from the web. There is no easy pull down menus to help you in your application. I was looking for an Integration. Pocket CAS did it just as well. In Mathematica I didn't have to reduce it myself. Wolfram alpha also worked without me doing the algebra to reduce it to a simple form. ### 5/5 — The best offline CAS on iOS you will find. *2014-03-17, version 2.1.3* Short of the Wolfram Alpha app, which requires an internet connection, you simply will not find a more powerful scientific computing platform on the iOS app store, and unlike Wolfram, a fully programmable one. However, there are still a few areas that could use improvement: 1) While the user-customizable macro keyboard is invaluable, there are a number of frequently-used symbols that can only be reached several levels into the system keyboard (notably ^,$,%,\). Adding these somehow to the numeric keyboard would be a great aid to usability. 2) Perhaps the biggest selling point of this app is the line-by-line compatibility with both REDUCE and gnuplot. However, short of pasting code into the editor, I've yet to discover any way to import these files from a PC. Perhaps either dropbox integration or harnessing the iOS open-in functionality would solve this. ### 5/5 — Love it! *2013-10-08, version 1.6.8* Run gnuplot scripts unchanged. Reduce is elegant and powerful. ### 5/5 — Computer algebra system delivered *2013-01-13, version 1.4.5* Whoever doesn't like this software probably didn't know that it's CAS not a four function calculator. If you're modeling math or physics, this is a great tool for that purpose. ### 1/5 — Crap *2012-04-08, version 1.2.5* I'd like a refund on this crap, do not buy total crap. ### 5/5 — Brilliant! *2011-02-07, version 1.0.2* iCAS is an absolutely brilliant application. It is based on REDUCE, a Computer Algebra System (CAS) with a forty-year pedigree. It is much more memory-efficient than many competing systems, and thus performs very well on large problems (e.g., symbolically inverting a large n*n matrix, an operation that potentially produces n factorial intermediate terms). Doing simple tasks is very straightforward. There is a bit of a learning curve for some more complex operations, but that is in the nature of a full-featured CAS. I wholeheartedly recommend this as being the best of the CAS apps currently available for iOS devices. I only wish I had known about it sooner! ## Frequently asked questions about iCAS ### What is iCAS? iCAS is a native implementation of the REDUCE computer algebra system for iOS devices. It allows users to perform complex mathematical computations and generate plots offline, similar to desktop applications like Mathematica. ### What kind of math can iCAS do? iCAS can handle a wide range of mathematical operations including expansion and ordering of polynomials, substitutions, simplification of expressions, calculations with symbolic matrices, and arbitrary precision arithmetic. It also supports analytic differentiation and integration. ### Can I use iCAS offline? Yes, iCAS runs natively on your iOS device, meaning no internet connection is required for its core computational functions. This makes it ideal for use in environments with limited or no connectivity. ### Does iCAS support screen sharing? Yes, iCAS features screen mirroring support for iPhone 4/iPad and later devices. This allows you to share your results and plots with colleagues or use it for demonstrations in a class setting. ### What devices does iCAS support? iCAS is supported on iPhone, iPad, and iPod touch devices. It is designed to work across various device orientations. ### How often is iCAS updated? The latest version of iCAS is 2.4.5, which was last updated on March 14, 2020. While updates have not been frequent recently, the core functionality remains robust. ### What is the price of iCAS? iCAS is a paid application, available for $14.99. This one-time purchase provides access to all of its features without any in-app purchases or subscriptions. ### What is the age rating for iCAS? iCAS has an age rating of 4+. This indicates it is suitable for users of all ages, with no mature content concerns. ## Version history (last 1 release) ### 2.4.5 — 2020-03-14 • Internal optimizations. ## Apps similar to iCAS | App | Rating | Price | Category | | --- | --- | --- | --- | | [Thetis Tools](https://appshunter.io/ios/app/thetis-tools/id1460268980) | — | Free | Productivity | | [FairOrg LeadApp](https://appshunter.io/ios/app/fairorg-leadapp/id1460125760) | — | Free | Productivity | | [Your Ashford BC](https://appshunter.io/ios/app/your-ashford-bc/id1452979480) | — | Free | Productivity | | [OneTwoCount](https://appshunter.io/ios/app/onetwocount/id1454584180) | — | Free | Productivity | | [ZappID](https://appshunter.io/ios/app/zappid/id1455029820) | — | Free | Productivity | | [Filepick - File Manager](https://appshunter.io/ios/app/filepick-file-manager/id1460080480) | 4.7 (31) | Free | Productivity | ## More apps by Antonio Lagana - [i41CX+](https://appshunter.io/ios/app/i41cx-plus/id289068865) - [i41CX](https://appshunter.io/ios/app/i41cx/id292619450) All apps by Antonio Lagana: https://appshunter.io/developer/289068868 --- *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 2026-06-10.*