Systems, methods, and apparatus are provided that allow a user to draw and edit a chemical structure using one or more gestures performed on an input interface, such as a touch pad or touch screen. For example, the user may assign an atom label to a chemical structure representation by performing a press and tap gesture, change a chemical bond characteristic in the chemical structure representation by performing a tap gesture, and/or lengthen a molecular chain in the chemical structure representation by performing a drag gesture. The user may also rotate the chemical structure representation in the graphical display by performing one or more rotation gestures.