Katy Perry and John Mayer reportedly spent Memorial Day together at a barbecue at Katy's house, and the on-again, off-again couple appear to be back on...for now.

Two sources tell E! News that the two singers are now enjoying a "casual" relationship, and have been getting together "daily" since Memorial Day.  But don't call them boyfriend and girlfriend: one source tells E!, "They are just hanging out. They are not putting a label on it."

Katy is currently working on her next album, and John just started recording a new disc as well; he kicks off his summer tour on July 6.

Katy and John's relationship dates back to August of 2012.  After they started dating, they split up briefly, then got back together again, and started stepping out together publicly in December.  They attended President Obama's inauguration together earlier this year, and by that time, Katy was referring to John as "my beau" and "my boyfriend."  The two broke up in March, though, with John telling Ellen DeGeneres that "coupling" was "a tricky thing."