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. From replacements to the everyday pocket calculator to more powerful specialized scientific and graphing calculator apps, check out the best calculator apps on Android and iOS. (Image Credit: Georgejmclittle/Shutterstock)
PCalc Lite for iOS has a well-deserved spot on this list as a free, extremely flexible scientific calculator armed with powerful features. There are also 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 purchase additional features and operations through in-app purchases, or spring for the complete version for $9.99.
Calzy 3 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.
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.
Why should we be slaves to what a calculator looked like decades ago? That's the thinking behind Tydlig, an iOS calculator app that uses a smart and responsive freeform canvas that blends a calculator-tape style view with spreadsheet-style functions like linked numbers and retroactive corrections. Users can annotate numbers and calculations and print or export the canvas to PDF. There's even a graphing feature with a slider for easily tracing values of functions on the graph.
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.
Another solid iOS calculator alternative is Calcbot 2, a free calculator app and unit converter that combines convenience without skimping on features. The basic interface gives you the classic 4-operation calculator, but also presents a tape-style calculation history and an expression view for easy backtracking and editing. Turn your phone to landscape orientation to unlock scientific calculator mode. A unit conversion feature allows you to quickly transform 500 different units across 22 different categories (with auto-updating currency conversions), and a favorites key lets you save calculations and results for easy memory functions. An in-app purchase unlocks additional customizations, and the ability to define your own constants for ease of use.
All-In-One Calculator on Android is a nice calculator and formulary app that comes with your basic four functions plus some scientific calculator options. You'll also enjoy a variety of preset formula calculators running the gamut from algebra to geometry, unit conversion, and finance. Also included are basic memory functions, though with only one memory slot available, and a themable display. The app is ad-supported, with an in-app purchase available to turn off advertising.