ON a recent train journey, I heard a group of teenage boys (no older than thirteen) laughing uncontrollably.

Sitting close behind them, I could see them typing ‘porn’ and ‘sex’ into Google Images on their latest gadgets.

The pictures were uploaded instantly amusing for them all for the duration of their journey.

Before Christmas, David Cameron announced plans to help parents protect their children online, by setting a block on internet pornography and other dodgy websites.

The plans, so far, are aimed at parents who buy a new computer. They will be asked whether there will be children accessing the internet – if so parents will then be prompted to tailor filters on what they see.

But what about the billions of second hand computers that are already out there? What about the parents that don’t really take an interest in what their children look at?

With the latest smartphones and other gadgets – sorry Mr Prime Minister, sir, great idea – but somehow I can’t see this working 100 per cent.

The world wide web is a huge (and scary) place and a false date of birth or an easily-accessible password can take any child to the darkest of places.

Appointing mother-of-three MP Claire Perry, David Cameron said she is "a passionate campaigner for internet safety”.

She aims to get internet service providers on board to prevent children from looking at age restricted websites.

But sadly I don’t think even the most sophisticated ‘cotton wool’ smart phone app will prevent today’s children from accessing anything they want to see.

Especially when the curiosity is just at their fingertips.