identify/treatment for orange/yellow spots
Apples are very susceptible to pest and disease problems and eventually require a spray schedule for control. Based on your photo you are dealing with a rust disease. http://extension.umd.edu/hgic/plants/diseases-apples-and-pears
See our publication on pome fruit for more information and our website for growing information as well as spray schedules. Look at the spray schedule from Va Tech on rust and you will have to spray based on the disease and timing of application.