CITIZEN Calculator Ad-free is a paid version of the popular citizen calculator app on the Play Store. It is a fully functional emulator of the Citizen Calculator model CT-555N/ CT-555W. This calculator is ideal for general and business purposes and has a check and correct feature, which is useful for verifying long calculations without re-entering the values.

The app includes basic math operations such as addition, subtraction, multiplication, and division, along with percent calculation, tax calculation, memory calculation, price mark-up and mark-down calculation, constants calculation, and number formatting. The number formatting feature is based on the device locale and supports decimal and digit-grouping. The app also allows for auto replay and grand total calculation (GT).