Here is the logo and text of the official prayer for World Youth Day 2016 in Krakow.
“God, merciful Father, in your Son, Jesus Christ, you have revealed your love and poured it out upon us in the Holy Spirit, the Comforter, We entrust to you today the destiny of the world and of every man and woman.” 
We entrust to you in a special way young people of every language, people and nation: guide and protect them as they walk the complex paths of the world today and give them the grace to reap abundant fruits from their experience of the Krakow World Youth Day.
Heavenly Father, grant that we may bear witness to your mercy. Teach us how to convey the faith to those in doubt, hope to those who are discouraged, love to those who feel indifferent, forgiveness to those who have done wrong and joy to those who are unhappy. Allow the spark of merciful love that you have enkindled within us become a fire that can transform hearts and renew the face of the earth.
Mary, Mother of Mercy, pray for us. Saint John Paul II, pray for us.
 John Paul II, Homily for the Dedication of the Shrine of Divine Mercy, Krakow, 17 August 2002.