Nick Herbert has come up with an unusual solution to a problem many parents encounter as their child becomes a teenager — getting his son to respond to his text messages.

When he gave his son more freedom around the age of 12, Herbert had one request: check in throughout the day. But his son, Ben, was often busy playing video games with friends and would leave his phone on silent.

The frustrated dad would send text after text, hoping for an update on his son's whereabouts, but most of the time his messages went unanswered.

"By the end of last summer I thought, 'Well, there must be something better,'" Herbert, who lives in London, told CBS News. "I'm trying to find him all the time."

That's when Herbert came up with the idea for ReplyASAP, an app that allows you to send urgent texts that cannot be ignored.

"I wanted to be able to set an alarm on his phone — that was the gem of the idea," Herbert explained. "Alarms sound even on silent. Why can't I set an alarm on his phone in order to do that?"

He hired a friend to help develop the app, which triggers an alarm that will sound until a text is read.

In order for the alarm to work, the parent must download the app and invite the child to also download it. After the child accepts, both parties can start sending each other "ASAP messages."

The app is free to download, but users will have to pay for bundles, starting at $1.27, depending on how many people they want to connect with.