Man and woman sitting back to back, using cell phones

Two men sitting back to back in chairs

People sitting on stairs, low angle view

Man sitting on stairs, woman coming up stairs, high angle view

People in room with seats, low section, blurred motion

Woman carrying smartphone in back pocket

Couple sitting, smiling at each other, woman using cell phone, man wearing headset

Young couple sitting back to back at poolside

Woman sitting beside potted plant, using cell phone

Young couple sitting back to back at poolside stretching

Young couple sitting back to back at poolside, portrait

Young travelers sitting in back of pick-up truck

Young couple sitting back to back at poolside stretching

Professional man reclining in armchair, head back, on the phone

Young couple sitting back to back at poolside, arms raised

Group of hikers sitting in back of pick-up truck

Couple sitting side by side, both using cell phones, smiling

senior couple sitting back to back

A group of young people holding cell phones and personal digital assitants

A woman crying and smoking in the back seat of a car while talking on a cell phone

couple taking rest together

man rest his head on his lover's lap

A girl looking back on gift boxes with other students behind

A bank teller using a stool to help relieve lower back pain

Rear view of people at money exchange counter

Illustration of friends text messaging through mobile phone while standing back to back against whit

A woman talking on a cell phone in front of a house

Young men and woman playing cards on floor in the living room

Rear view of businessmen

Man and woman sitting back to back, exchanging cell phones