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app – n. a mobile phone program that performs a special function
button – n. a switch you press to control a piece of equipment
flap – adj. to move up and down quickly and repeatedly
mobile – adj. able to move or be moved easily
annoy – v. to make someone slightly angry
species – n. a group of animals or plants that are similar and can produce young animals or plants
monitor – v. watch something carefully
crowdsourcing – n. he act of giving pieces of work to a large group of people or to the public in order to gather information
