Who Are the Singers on the I Heart Radio Television Ads?

"I see the I 'heart' radio ads on television, and I'm curious who the singers are.  Can you help me?"  The Newton Falls Public Library staff member was not familiar with the commercials, so more information was needed from the patron.  He said he knew that one of the singers was Usher.  Of the others, one was a British boy band.  The others were a white lady with dark hair and a dark skinned lady with white hair.

There is currently a very popular British boy band named One Direction. Looking at their website, www.onedirectionmusic.com, our patron recognized them as the group in the commercial.  Our staff then looked for information at www.iheart.com, but there was no information about their commercials.  Because television is such a visual medium, we felt that doing Google image searches would bring up an assortment of photographs.  From these our patron was able to identify Katy Perry and Nicki Minaj as the other two singers.