But if you've been spending hours on the phone to your mates it's worth giving your smartphone bill a check.

Unlike regular calls from your phone, WhatsApp uses data to put you in touch with friends and family.

This of course is no problem if you're hooked into an unlimited WiFi hotspot, but if you're using your phone's 3G of 4G signal you could be in for a shock.

On a recent test by AndroidPit, it was discovered that WhatsApp calls can use up to 1.3Mb of data per minute.

At this rate, someone with a 500MB data plan would be through their month's limit after just six hours on the phone – that's just 11 minutes per day.

This issue isn't unique to WhatsApp, as other internet calling services including FaceBook Messenger, Google Hangouts and Apple's FaceTime will all much through your data.

Having enough data is becoming a growing issue for many smartphone fans.

Internet calling, on demand video content and music streaming mean Brits are using more data than ever.

Unlimited calls and texts are now common on most contracts but data is still limited and, if you want plenty of it, you'll have to pay a hefty price.

For example, a new 16GB iPhone 6 contract with 10GB of 4G data will set you back around £50 per month.

Most affordable contracts only offer between 500MB and 1GB of data, which is often woefully inadequate and may leave you having to top up your data each month.

Daily Star Online recently tested how much data is used downloading content from popular services such as Netflix and Spotify.

And if you want to know where your data is disappearing each month here's the results.

(dailystar.co.uk)