All In One Calculator is a free, speedy, and simple calculator app that offers a wide range of features. It is a perfect app for professionals from various fields. This app offers a simple calculator with a large font and a scientific calculator that supports many scientific operations, such as trigonometric, logarithmic, exponential functions, and more. Additionally, it has a history feature that can store up to 1000 calculations.

The app also offers an engineer mode, which includes a unit converter that supports a large number of engineering units with a pro and advanced one-click conversion method. It supports both metric and imperial measurement systems. The app is also equipped with a finance calculator that includes billing, GST pro/sales tax/VAT, and custom rate support. It also has a tool section that includes a fuel calculator, compass, protractor, cooking, and counter. In the next update, the app will add full construction calculator features.