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app – n. a computer software program for a smartphone or other electronic device
delivery – n. the act of transporting something to someone
casual – adj. easygoing; unofficial
ghost – n. the spirit or presence of a dead person
fund – n. a financial or investment program
rent – v. paying someone for the use of something
customer – n. someone who purchases a product or service
convenience - n. a quality or situation that makes something easy or useful for someone by reducing the amount of work or time required to do something
concept - n. an idea of what something is or how it works
