One of the biggest drivers of in-store sales on eBay and other retailers is the company's scanning app Red Laser.
But an average urban worker in Nairobi also spends one-third of his or her salary on getting to work -- so the lack of transit is also one of the biggest drivers of urban poverty.
One of the biggest drivers of wireless competition today is Google's Android operating system.
"One of the biggest drivers is China," said Mark Edelstone, a semiconductor analyst at Morgan Stanley.
One of the biggest drivers for this stylistic change is being forced upon designers by the constraints of smartphones.
A recent UN report pointed out that group solidarity is one of the biggest drivers of violence.
"One of the biggest drivers is deindustrialisation," explains James Meadway, senior economist at the New Economics Foundation.
To balance the budget in the face of ever-increasing tax cuts would require untenable near-term cuts in Medicare, one of the biggest drivers of budget imbalance.
The channel is seemingly aimed at children, who have become one of the biggest drivers of YouTube viewing over the last two years.
Britain's monarchy, including royal heritage and property, is one of the biggest drivers of tourism into the UK, generating an estimated £500m a year from overseas tourism spending.
One of the biggest drivers of complaints - and source of some of the most significant malpractice - involved the inappropriate use of bed and breakfast accommodation, particularly where children were involved.
