The RDev Calculator is a standard calculator with some advanced features:
* Multiple Themes with configurable button text color and sizes
* 'Standard buttons only' option allows for larger buttons
* Status Display shows what calculations were used for the displayed result
* Comma Formatting
* Expression Mode
* Percent Button
* Currently displayed item is editable by tapping the display or using arrow keys
* Parentheses
* Programmable Function Button (defaults to "X + 15%%%%" for a tip)
* Haptic Feedback
* Results and expressions can be copied to the clipboard
* Ability to keep screen on while working in the calculator
* Decimal Precision setting
* Results history showing the last 10 results
* Results larger than can be shown in the main display can be viewed in results history or edit mode
* Memory and history is saved between app instances
* App can be saved to SD Card on devices running Android 2.2 or greater