Tap - to touch the screen of an electronic device as a means of inputting a command
Dot - a small round mark
Thumbnail - a small image which can be expanded
Swipe - to move a finger across a touchscreen on an electronic device as a means of inputting a command
Whitebalance - A feature many digital cameras and video cameras use to accurately balance color
Capturea picture - to take a photo
Snap - to take a snapshot of (something)
Default - the preset selection of an option offered by a system, which will always be followed except when explicitly altered
Shutter - a device that controls the duration of an exposure by opening and closing, allowing light to reach the film or plate for a specified amount of time
Definition of dot from the Collins English Dictionary [