This weekend on The iHeartRadio Countdown with Mario Lopez the incredibly talented Charlie Puth will be stopping by the show! He just dropped a brand new song called 'Attention' and he's about to hit the road with Shawn Mendes this Summer. So we'll catch up with him and Countdown the top 20! Rumor is Ed Sheeran may have finally been dethroned after 13 straight weeks at #1! Tune in!