More than 90% of UK mobile users cannot get through the day without using their phone, a survey suggests.
Mobiles have had a huge impact since their launch 21 years ago
Among younger users, 9% admitted being addicted to their phones and feeling out of control in how they used them, the Yougov poll of 16,500 people found.
The study, commissioned by Carphone Warehouse, also found many women relied on their phones as a form of security.
Fifty-four per cent of females under 25 had used a mobile when out alone to put people off approaching them, it found.
The mobile has become a new "barrier" for women to fend off unwanted attention, where a newspaper or magazine would have been used in the past, the study said.
Overall, 21% of the people polled admitted using a mobile as a means to stop people approaching them.
Mobile phones have also become a greater focus of crime - approximately one in 10 people have had their handset stolen, with 18 to 24-year-olds most at risk, the report says.
Half of those quizzed said they would use their mobile to record evidence of a crime, while 47% said they would record a crime in progress.
The Mobile Life report - the biggest study of the UK's mobile users - also describes six tribes of mobile users:
- Generation Mobile - single style conscious 18 to 24-year-old students or young adults in their first job
- Phonatics - single 18 to 34-year-olds who see a mobile as their most important electronic possession.
- Practical Parents - cost-conscious young families under the age of 34 who choose their mobiles on price grounds
- Fingers and Thumbs - married, middle-aged or retired people with children or grandchildren
- Smart Connected - affluent families and professionals aged 25 to 44 who use mobiles to organise their work and social lives
- Silver Cynics - affluent, married parents who are approaching retirement
The survey, carried out with advice from the London School of Economics and Lord Philip Gould, found 92% of mobile owners cannot get through a typical day without using their phone.
While most people aged between 18 and 40 say mobiles have improved their lives, the over-40s are evenly divided on this question.
The younger generation puts their mobile ahead of television, with most 18 to 24-year-olds thinking it matters more to them than their TV.
The survey also found only 14% of people would turn their phone off during sex.
While 75% of people think it is rude to use the mobile during dinner, only 9% of respondents said it was unreasonable to do so on a train.
Recycling campaigns have a long way to go, according to the survey.
The UK has a huge number of old mobiles lying around people's houses, with one in three people hanging onto outdated models instead of recycling or disposing of them.