You text, you pay. That's a business model that's worth 23 billion dollars to the phone companies that provide text messaging.
But now savvy texters are increasingly finding a way not to pay.
Free text messaging is taking off, and one of the top providers is Gogii, a company based in Marina del Rey.
Their app is called TextPlus which can be downloaded to a smartphone, and it works just like regular texting.
The text is free to users, and the company makes money through advertisements.
Textplus has been downloaded by 20 million people since it started in 2009.
"We knew we were going after messaging. It's actually a 20 year old medium, but there's been no innovation in it," according to Scott Lahman, CEO of Gogii.
The innovation includes group rooms, where texters can chat about their favorite movies.
Every Textplus user gets their own phone number, which allows them to text those who don't have the app.
Apple's upcoming iMessage service and Facebook's new Messenger app are other no-cost options which could diminish a revenue stream for the wireless industry.
Those companies haven't yet commented on their new competitors, but their revenue from text messaging has been slowing down thanks not only to the free app's, but to the increasing use of smartphones with easy email applications.
But even the folks at Textplus don't think they'll be knocking out Verizon and AT&T anytime soon.
I don't see it going away. I just see it being about more choices," says Lahman.