Another trend is growing demand for same-day delivery, which has been a boon for independent express parcel delivery services such as Want it Now.
"When it all started it was all about free delivery and now consumers want it now," says Mr Hopkins. "People are willing to spend $20 to $30 to have something delivered that day."
Increasingly, online shopping is going mobile, with sales from iPads up 363 per cent in two years, iPhone sales up 377 per cent and android sales up 345 per cent.
Mobile commerce now represents over 35 per cent of sales," says Mr Harper.
"That's grown quicker than anything else - people are couch shopping, sitting in front of the TV and shopping on their iPads during ad breaks," he says.
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