Forget cocaine and alcohol we are hooked on our phones and it's bad news, says an expert in marketing.

LISTEN ABOVE: Adam Alter, author of Irresistible and professor at New York University, spoke to Rachel Smalley

Adam Alter, a professor at New York University, says we touch our phones an average of 2617 times a day - equivalent to around three hours of swiping and scrolling.

Alter, who has just released a book called Irresistible - the rise of addictive technology and the business of keeping us hooked - told Rachel Smalley the reason for our addiction is the access it gives us to email and social media.

"I think they do a lot of things for us simultaneously in one device - they are a vehicle to so many different very addictive experiences."

Alter said those experiences provide us with mixed feedback - something that humans find irresistible.

"You never know when you are going to get your next email and you don't know which Instagram photo will attract a lot of likes or very few.

"It's a portal to a very addictive world."

Alter said humans crave positive attention from other humans and surprisingly we like it most when we receive both positive and negative feedback.

"Ostracision is the worst thing that can happen to you."

"So any vehicle that gives us access to millions of people at a time - which these social networks do - is very hard for us to resist."

While positive feedback sounds like a nice ideal, getting both positive and negative makes the positive feedback so much better and makes it addictive.

"What we look for is a little bit of uncertainty because when we do get that flush of positivity - just as a gambler does when they sit in front of a slot machine - that is really a very appealing experience and it is very hard to resist that."

And he said social media businesses are well aware of what they are doing.

"They wouldn't call it addiction. The way they measure it is through time on device."

Alter said social media businesses hire behavioural experts to tweak things to make them as addictive as possible.

The classic example of this is the Facebook 'like' button.

"It was only introduced several years into Facebook's life and it changed the way people engaged with Facebook to make everything feedback related and made Facebook much harder to give up."

Alter says all this online interaction comes at a cost.

"Obviously relationships online are a little bit impoverished compared to real ones. We don't have the full range of emotions, we can't convey things as subtle or in as much nuance as we can when sitting face to face."

"It robs us of the interaction we have in the real world."

Alter said the biggest concern is for kids who are using the technology at a time when they should be developing real life communication skills.

So what can we do about it?

Put the phone away, said Alter.

"Remove temptation. Whether that means between the hours of 5pm and 8pm you will make sure the phone is in your drawer."