Welcome to the new episode of the Billboard Pop Shop Podcast, your one-stop-shop for all things pop on Billboard's weekly charts. In addition, you can always count on a lively discussion about the latest pop news, fun chart stats and stories, new music, and guest interviews with music stars and folks from the world of pop.

Casual pop fans and chart junkies can hear Billboard senior director of charts Keith Caulfield and Billboard deputy editor, digital Katie Atkinson every week on the Pop Shop Podcast, which can be streamed on Billboard.com or downloaded in iTunes . ( Click here to listen to the previous Tuesday’s edition of the show on Billboard.com).

Today on the show, we chat with Mark Foster of Foster the People! The frontman called in to the Pop Shop from the road to talk about the slow-burning success of the group's crossover hit "Sit Next to Me." Though the single and its parent album, Sacred Hearts Club, were released a full year ago in July 2017, "Sit Next to Me" is now a top 20 hit on Billboard's Pop Songs chart after rising to the top five on Hot Rock Songs in May.

"It's been kind of amazing, really, just because it's been really surprising for me," Foster says of the song's climb. "Every week now, I’m just getting an update that it's continually growing at radio. I'm just like 'What? It's been on the radio for like eight or nine months!' And it's just cool that it's connecting with people."

This is hardly the first time Foster has been surprised by radio: Back in 2011, Foster the People saw their breakthrough hit, "Pumped Up Kicks," climb to No. 3 on the Billboard Hot 100, thanks to the song's crossover appeal on pop radio. "'Pumped Up Kicks' kind of came out of nowhere and continued to kind of surprise everybody, including myself," he tells Pop Shop. "I never in a million years thought that that song would be played on the radio at all, let alone be played on pop radio and be heard around the world."

In fact, the rise of "Pumped Up Kicks" seven years ago paved the way for songs like "Sit Next to Me," and other rock artists making the move to mainstream top 40. "At that time, especially on pop radio, you rarely even heard guitars on pop radio, let alone a band," Foster recalls. "Pop radio normally kind of super-serves a pop artist, a singer or a rapper and something with more of an electronic production, but you rarely hear a band. So that song was pretty -- I would say it was really luck-centered, kind of came out of nowhere. Radio was in a very different place back then. From that point, I would say that radio started to come around, and I would say that even that song opened up some doors for bands to be heard on pop radio a little bit more. You could see with like Gotye and then Capital Cities and then Arctic Monkeys ... and then obviously last year Portugal. The Man."

Foster is hoping to push the rock boundaries even further by channeling the collaborative spirit of hip-hop, inspired by the omnipresent Drake. He wondered: Why can only pop stars and rappers collaborate? So he and his Foster the People bandmates teamed up with The Knocks for their new song "Ride or Die."

"With someone like Drake, it's just his name is always on the radio. He's always got something new coming out, it's been like that for years -- whether it's his own stuff or whether he's collaborating and jumping on somebody else's track, which is something that I think, in the end, [we should] do more often. I would love to do a song with Portugal. The Man, I'd love to do a song with Cage the Elephant. I would love to do a tune with MGMT, I would love to do something with Vampire Weekend or Arctic Monkeys. ... It doesn't have to be all like lone wolf, super competitive, super secretive. We're lucky to be able to make music and I find it to be really fun to collaborate with people that come from a different background from myself. So that's something that I think in the future something that I'm really kind of shooting for."

On Wednesday, Foster the People play their latest date on Paramore's After Laughter tour, hitting The Forum in Inglewood, California. While the two bands didn't know each other before launching the tour, they've become fast friends, thanks to some very kumbaya activities. "We all got along right away, and it's been kind of funny too, 'cause the last few venues we played with them had kind of like summer camp vibes," Foster says. "Like the venues themselves have had like ping-pong and bonfires afterwards with s'mores and like weird bicycles and scooters and all this stuff laying around and basketball hoops and whatever. So it's even kind of like before the shows and after the shows, we've all just been kind of like hanging together doing weird activities." Find all of Foster the People's tour dates here.

Also on the show, Keith & Katie chat about Drake's domination of the Billboard Hot 100 and Billboard 200, Ariana Grande's epic "God Is a Woman" video, and the 2018 MTV Video Music Awards nominations.

Listen above and click here to subscribe/rate the Pop Shop Podcast on iTunes.