How would you feel if your phone could predict your next action and support it by highlighting the relevant areas on the screen? In a study, we ask users to find an app on a smartphone and implemented a simulation of a supporting system. On this account, the target app visually popped out in some of the trials. Results showed that users were significantly faster and gave higher UX ratings, when their search was supported. Moreover, 80% of the users indicated that they would like to have such a system on their smartphones. The demand dropped to 22% due to privacy issues after we explained that such a system could be based on an algorithm learning the user’s typical behavior. We conclude that explicit information on manner of functioning and transparency regarding data streams are essential when designing adaptive systems to ensure the fulfillment of user needs.