The US government wants smartphone manufacturers to adopt a common ‘driver mode’ that would stop the most distractive apps from running. The voluntary guidelines would be a one-stop mode along the lines of the common airplane mode on phones.

The National Highway Traffic Safety Administration is making the proposals for handsets as a follow-up to existing guidelines for technology built directly into cars. As with those ideas, the idea is to persuade rather than force manufacturers to take action.

Transportation chief Anthony Foxx said the move was needed because many app developers don’t take into account the possibility of people using the app while driving.

The idea is that the driver mode would lock out any apps or features that require a certain level of visual attention, with the proposed threshold being more than two seconds at a time, or more than a total of 12 seconds to complete a task. Those figures are derived from measurements of the time it takes to tune a radio on a car dashboard, a task that’s been used as the maximum safe amount of time to take your eyes off the road.

Driver mode would also mean phones would switch to a simplified user interface when activated, likely with larger icons and text to reduce the time spent finding key options. The drawback here would be that people would need to go through more screens to achieve a particular task.

In most cases it would be up to drivers to enable “driver mode” in the same way as passengers manually switch on flight mode on planes. However, the NHTSA says driver mode should be activated automatically when a phone is paired with a car’s entertainment or control systems.