Many mums and dads will worry about the sheer amount of time youngsters spend on their smartphones.
As adults know only too well, the devices can be utterly addictive, as they offer internet access and an endless selection of apps and games.
But parents might want to place limits on how long their kids spend on their phones for many reasons.
Perhaps they're not spending enough time doing physical exercise or enjoying the company of their friends, or maybe they aren't doing their homework and their grades are suffering.
Alternatively, children might be spending all night on their phones and not getting enough sleep as a result.
Japanese firm Tone Mobile Inc has therefore devised a smartphone that only works during daytime hours, so there's no risk of kids overusing them.
The Tone m17 will be locked between 10pm and 6am for under-12s, while access to messaging app Line will be limited.
Furthermore, the device will automatically lock in pre-registered locations such as schools, so kids couldn't be tempted to check their smartphone during lessons.
Parents will be able to alter the settings if they wish, so they have control over exactly how long the device will be locked for.
Tone Mobile Inc will release the phone in Japan at the beginning of August and we're interested to see how well it performs.
After all, overuse of smartphones among kids is by no means a problem confined to Japan, so could this device be rolled out elsewhere further down the line?
If it's an overwhelming success, could other manufacturers follow suit and introduce other child-friendly smartphones?
We look forward to finding out!