Clear Channel’s iHeart Radio group has announced the set of performers and nominees to be featured at the first annual iHeartRadio Music Awards show, to take place in Los Angeles on May 1st.

Reservoir catalog performers Rihanna and Justin Timberlake go head to head in the Artist of the Year category, while rowdy “Girlfriend” duo Icona Pop is up for Best New Artist and Rihanna’s ‘Navy’ is recognized among contenders for Best Fan Army. Other names from the Reservoir collection–Avicii, Calvin Harris, Drake, Macklemore, and Tim McGraw–are sprinkled throughout the remaining awards categories.

Performers at the awards will include “Empire” singer Shakira, Grammy winner Drake, and “Problems” rapper Kendrick Lamar.

Fans can visit the official awards page to vote for their favorites in each categories.

UPDATED 5/2/14: The unstoppable Rihanna took home the ceremony’s Artist of the Year title, that win and that of the Rihanna Navy for Best Fan Army solidifying her reign over pop. See the complete list of winners, which included Avicii for EDM Song of the Year, here.