A non-transitory computer-readable medium having a computer program readable by a computer of a portable device connectable to an image input device and image output device and including a memory storing external programs activated by the computer program, the computer program causes the portable device to perform: receiving a user operation on a first screen including first objects corresponding to the external programs; determining the designated program when the first object is designated; when the designated program has a first function of executing processing for the input data, instructing the image input device to execute an input operation and performing first post-processing; and when the designated program has the second function of enabling a user to designate the output data, performing pre-processing and controlling the image output device to execute output operation for the output data.