How can one avoid wasting time on what is not beneficial, especially when using a mobile phone?

A Muslim should fill his time with what benefits him in his religion and his worldly life, because he will be questioned about his time on the Day of Judgment. Wasting time is a form of divine punishment, and it is more severe than death because it severs a person from God and the Afterlife. Among the forms of wasted time are: not benefiting from knowledge one does not act upon, performing deeds without sincerity, possessing wealth from which one does not spend, having a heart empty of God's love, having a body idle from His obedience, having time that is not used to catch up on what was missed, and having thoughts that wander in what is not beneficial. The greatest wastes are the waste of the heart and time, and these are the root of all waste. Organizing and scheduling time, by allocating specific time for each matter, helps in utilizing time effectively.