Apple (APPL) compared the cost of buying the Alphabet (GOOG) mapping app against the cost of making its own mapping app. In addition, Apple considered the loss of sales to Alphabet’s smartphones because of the lack of voice-directed, turn-by-turn navigation, which Alphabet would not provide to Apple. Finally, Apple considered the loss of sales that would occur if its own in-house iPhone app was of inferior quality.
By making its own app, Apple had access to location data collected from its iPhone users. These data would prove valuable for product marketing. Apple was also concerned about the growing popularity of Android phones. Apple was worried that its market share could drop significantly if Android phones had an important feature that Apple phones did not.