This story has been updated since it was orginially posted.

Wireless and high-tech giants will announce Tuesday a ratings system for mobile apps to warn families about smartphone and tablet software that contain violent and other mature content.

AT&T, Microsoft, Sprint, T-Mobile USA, U.S. Cellular and Verizon Wireless will be the first companies to adopt a standard ratings system modeled after one used by video game makers, according to wireless trade group CTIA.

The system, set by the Entertainment Software Ratings Board, will categorize apps by those appropriate for everyone (6 and older), everyone 10+ (ages 10 and older), teens (13 and older), mature (17 and older), and adults only (18 and older).

There are no government regulations on mobile app ratings. Apple sets age guidelines for apps in its iTunes stores. Google Android developers assign ratings on their apps according to age groups. Neither firm is part of the initiative.

CTIA president Steve Largent said in a release that the effort is meant to give better tools to parents, as children and teens flock to mobile devices for games and entertainment.

Many apps and wireless companies have warned against any federal regulation.

“It’s a win-win when industry takes proactive, responsible steps to protect children from inappropriate content,” said Sen. Mark Pryor (D-Ark.) in a statement.

Common Sense Media, a nonprofit group that advocates for the safe use of media by children, rates mobile apps for content and has found that current rating systems by Apple and Google can be misleading or inaccurate.