If you're a smartphone junkie, this iPhone case rations your screen time

This phone case shuts off your screen when you've used your phone too much. Photo / 123RF

Many of us seem to agree that it's not ideal to be constantly engrossed by our smartphone screens, but quite often, temptation proves too great.

There are a number of apps available that offer to monitor your screen time and police how much time you spend on your device.

But apps like BreakFree or bSocial mainly just provide pretty graphs about usage and send push notifications telling you to put down the phone.

A Japanese company has come up with a more forceful and simple solution: a phone case that shuts your iPhone screen off when you've used it too much.

The case is aimed at parents looking to curb their kid's iPhone addiction, but could also be used by adult smartphone users struggling with self-regulation.

It's called Otomos and the case is fixed to the phone and cannot be removed without a special screw - making it ideal for controlling parents.

The case has sensors and pairs with an app on the iPhone to allow parents (or clear-minded phone addicts) to limit daily usage on the phone.

Once you've reached your daily limit, the phone will automatically enter sleep mode. It even has motion sensors designed to prevent use when somebody is walking.

"We have developed the product after hearing many views and concerns of parents who have children using smartphones," Masato Otsu, president of Momo Ltd, told the Japan Times.

The smartphone case previously raised more than $11,000, reaching it goal on Japanese crowd-funding platform Makuake.

Currently, it only works for iPhones but the premise of the case could be one that proves rather popular in our increasingly screen-obsessed society.