The computational powers of smartphones and tablets have made the humble pocket calculator pretty much obsolete. Now even more specialized tools, such as scientific and graphing calculators, are under threat by the proliferation of highly capable calculator apps.
Whether you're looking to replace your phone's built-in calculator or you need a specialized scientific calculator, check out the best calculator apps on Android and iOS.
Pcalc Lite (iOS: Free, with in-app purchases)
PCalc Lite for iOS has a well-deserved spot on this list as a free, extremely flexible scientific calculator armed with powerful features while also giving you the option of numerous add-ons. The basic package gives you a fair amount to work with, such as trigonometric and logarithmic functions, a radian mode, undo and redo operations, as well as unit conversions and constants. Users looking for more power can buy additional features and operations through in-app purchases, or spring for the complete version for $9.99.
Download PCalc Lite: iOS
Calzy (iOS: $1.99)
Calzy takes a neat approach to calculator apps with a "Memory Area" for quickly saving and labeling calculations, variables and other bits of data that you might want to store for easy reference across multiple sessions. The app also includes a configurable keyboard, 3D touch support, scientific functions, history and bookmarking, as well as multitasking support. It's an excellent all-around calculator app, and it's no surprise that Apple recognized it with a design award.
Download Calzy: iOS
Calcularium (iOS: Free)
InVooDoo’s Calcularium combines some neat controls with powerful tools for inputting and editing your calculations. The result is a calculator app that’s easy to use while also featuring some great functionality under the hood. Users can plug in the numbers with the traditional keyboard or input equations through voice or photo mode, and then label each number and variable for quick search and recall. Gesture controls let you rearrange elements of each equation, and you can save formulas and variables or break down individual variables into sub-equations. Calcularium does come with a lot of features, making the built-in video tutorials narrated by Siri a particularly useful function.
Download Calcularium: iOS
Soulver (iOS: $4.99)
Soulver is another popular iOS calculator replacement that mimics some of the best features of tape-style office calculator while offering digital extras. Soulver displays all of your calculations in a straight column, allowing you to quickly reference previous calculations, while an editing cursor allows you to go backwards and forwards to change lines, with each modification automatically updated downstream. The app includes support for custom labels, unit and currency conversions and users can save their sheets and share them or work on them later.
Download Soulver: iOS
Numerical 2 (iOS: Free)
Numerical2 is an app without equals, literally. The app speeds up input by doing away with the equals button, as well as automatically applying brackets to operations. It's not just about speed though. Numerical fields scientific calculator functions as well as fraction operations and special numbers such as Pi, E and infinity. The app supports landscape mode, split-screen multitasking, and even includes a custom keyboard for doing calculations within another app. On top of all that, Numerical also comes with multiple themes and a theme maker.
Download Numerical2: iOS
HiPER (Android: Free)
Rather than aim for the generic calculator experience, HiPER focuses like a laser beam on delivering an excellent scientific calculator app for Android smartphones and tablets. Mimicking the layout of traditional scientific calculators, HiPER includes both basic arithmetic operations as well as a dizzying arsenal of functions and special features, including fraction operations, mixed numbers and more, all with a built-in help feature to aid users in making sense of things. HiPER supports a variety of layout options optimized for phone screens and tablets. To get the most from the app, you’ll need to either enable ads or spring for the $3.49 Pro version, which unlocks expression mode, graphing, expanded precision (100 significant digits, 9 digits of exponents) and symbolic computation.
Download HiPER: Android
Scalar (Android: Free)
It seems almost a shame to just call Scalar a calculator, as this Android app does a ton more. Certainly, it’s a capable scientific calculator, with arguments, functions, user-defined functions, arguments and variables. But what makes Scalar shine is its script creation and editing tools for automating routine or advanced calculations, complete with syntax aides to help you organize your script writing. Scalar is ad-supported, with a $2.99 pro version removing advertising and offering premium features like expanded script editing and saving options. While it would be overkill for splitting the restuarant tab, Scalar is a powerful and interesting app to explore for users doing more complex math.
Download Scalar: Android
Mobi Calculator (Android: Free, $3.49 Pro Version)
Mobi Calculator (formerly CubeCalculator) has been a long-time staple for Android users looking for a powerful and customizable calculator app. The main screen covers your basic arithmetic operations and parentheses, as well as two customizable buttons. A Mode button provides access to trigonometric and logarithmic functions. The app's settings menu provides hexadecimal, binary and octal support, as well as a viewable 50-line operation history. The $3.49 pro version allows for a 1,000-line history, support for five-line expressions, and additional visual themes.
Download Mobi Calculator: Android
Calculator ++ (Android: Free)
Calculator++ is another high quality, feature-packed Android calculator that comes loaded with tons of operations, variables, modes and settings sure to warm the heart of a dedicated cruncher. It's your scientific and graphing calculator all wrapped up into a single convenient, mobile package, with an equation editor, operation history, built-in and user definable variables, automatic expression simplification, complex calculations, a windowed mode and more. Calculator ++ is ad-supported, but only displays ads in its secondary screens.
Download Calculator++: Android
Desmos Graphing Calculator (Android, iOS: Free)
Desmos Graphing Calculator is a free, powerful graphing calculator app that covers a wide variety of graphing functions and works fully offline without any problems. Users can input functions to display on a graph (with options for the Cartesian, polar, and parametric coordinate systems), using sliders to animate parameters, view output tables, input points, find the best fit line and more. It's a feature-packed graphing calculator that's perfect for the student on a budget.
Photomath (Android, iOS: Free)
Photomath turns a phone's camera into a calculator, with users able to use their camera viewfinder to scan and instantly solve math problems. Scan a problem, and the app displays the final answer along with a step-by-step breakdown of the problem's solution so that you can learn how to figure out solutions on your own. Photomath provides support for alternative answers, as well as a smart calculator for editing scanned equations and a new graphing mode. The app handles everything from basic algebra to linear, quadratic, and absolute equations and inequalities, systems of equations, trigonometry, and more with equal aplomb.
Wolfram Alpha (Android, iOS: Free)
It may seem a disservice to the power of Wolfram Alpha to lump it in among calculator apps, but the app deserves a place here because Wolfram Alpha's computational knowledge engine is a wizard when it comes to queries involving math, numbers, calculations and statistics (along with 29 other disciplines). Not only will Wolfram Alpha help you do the math, it'll also give you formula details, graphic representations and explanations for how the app got to the solution. The major downside? Wolfram Alpha needs an internet connection, so if you've got spotty mobile signal, you're going to need another backup calculator.
MyScript Calculator 2 (Android: Free; iOS: $2.99)
MyScript Calculator 2comes to the rescue of those of us accustomed to writing down equations on pen and paper rather than punching them into a calculator. A handwriting recognition system allows users to write down equations, with the app calculating the results. MyScript supports basic arithmetic, as well as percent, square roots, trigonometric (and inverse) functions, logarithms and constants such as pi and Euler's number. Version 2 adds extras like history, a memory function, multi-line support, dragging and dropping, and a ton of usability improvements.
CalcTape Calculator with Tape (Android: Free)
CalcTape Calculator is an excellent free app that draws inspiration from the traditional office tape calculator and improves on it. Users can enter a long string of figures and operations while being able to view their results in a scrolling tape, allowing you to keep track of a long calculation. You can go back and edit steps in the tape, with all operations down the line being automatically adjusted. Users can add text labels to individual steps in the tape, and the entire reel can be copied to a clipboard in order to be emailed or used in a word processor.
Digits Tape Calculator (iOS: $1.99)
Digits is a tape-style calculator for iOS devices that allows users to keep track of long calculations on a history reel, complete with text labels. Unlike a tape calculator, though, Digits allows users to go back in the calculation history and change operations or figures, with those changes automatically figured in down the line. The app particularly shines in its ability to print the tape reel or share it straight to email, VoiceOver accessibility support, and split view compatibility on the iPad, making for a handy office companion. Updates have added new features such as the ability to re-order entries and operations, and interface options like a Night mode in the Pro Design in-app purchase; another in-app purchase adds extended exporting options.
Download Digits Tape Calculator: iOS