It looks as if the no-phones trend at concerts and other performances is gaining ground as performers such as The Lumineers, Louis C.K., Alicia Keys, Dave Chappelle and others are using cell locking pouch Yondr to prevent device use at their shows. The case keeps the users' phone locked within a specific, non-usage perimeter, outside of which they can access their device.

Many performers are fed up with incessant use of cell phones at their performances, and would like the audience to be present in the moment to enjoy the shows rather than so focused on recording the moment for later that they miss it in the "now."

We first told you about Yondr almost two years ago when the company was still in its infancy. Concertgoers are each given a special locking pouch that keeps phones locked within a designated no-phone zone, outside of which the phone can be unlocked for their use. It appears the concept is now catching on with top performers, who have required its use at their shows. The system is especially useful at performances that highlight new material that has not yet been released to the general public, and which the artists want to retain control over.

Singers such as Alicia Keys have used Yondr when performing such new material, and comedians in particular like the protection they get from online leaks of their new jokes. Louis C.K. and Dave Chappelle have both implemented the system while trying out new material at comedy clubs.

Rock band The Lumineers just used Yondr this spring at a series of secret shows in which they sang brand-new songs from their upcoming, then-unreleased album Cleopatra.

"There was a large concern about the album being sort-of released via grainy video and leaked out online," said band lead singer Wesley Schultz, who expressed surprise at how open to the concept his fans were. "If you can set it up so that people can't get to their phones as easily or are deterred, people actually really welcome that. It's just such a strong force of habit in our lives right now."

That's not to say everyone has warmed to the idea. Schultz recounted the tale of one rebellious fan who unsuccessfully tried to slice into the Yondr pouch with a pocket knife. Still, the no-phones movement is gaining ground, with superstars such as Adele and Beyoncé having recently chided fans for using their devices at their concerts rather than enjoying the experience through their own eyes and ears.