Phone game apps are the most addictive but if you never download them you won't get into it. Games have 4 caracteristics that makes them addictive: winnable, it has goals, novel challenge that keep you in state of flow, feedback. These things could also be used in reading books and that becomes addictive in a good way.
Tl;Dr phone apps are the best thing to aquaire skills in the future. If you block or hide notification and not download addictive apps you will be fine.