Almost nine-in-10 pupils now have a mobile compared with fewer than three-quarters who have their own books in the home, it was disclosed.
The study by the National Literacy Trust of Great Britain suggested a link between regular access to books outside school and high test scores.
According to figures, some 80 per cent of children with better than expected reading skills had their own books, compared with just 58 per cent who were below the level expected for their age group.
The disclosure follows the publication of a study found that found keeping just 20 books in the home could boost children’s chances of doing well at school.
Research led by Nevada University, in the United States, said that children coming from a “bookish home” remained in education for around three years longer than young people born into families with empty bookshelves, irrespective of parents’ own education, occupation and social class.
Jonathan Douglas, National Literacy Trust director, said: “Our research illustrates the clear link with literacy resources at home and a child’s reading ability, as well the vital importance of family encouragement.
“By ensuring children have access to reading materials in the home and by encouraging children to love reading, families can help them to do well at school and to enjoy opportunities throughout their life.”
As part of the latest study, the trust surveyed more than 17,000 schoolchildren aged seven to 16.
It found that 85.5 per cent of pupils had their own mobile phone, compared with 72.6 per cent who had their own books. Among children in Key Stage 2 – aged seven to 11 – 79.1 per cent had a mobile compared with 72.7 per cent who had access to books.
The research comes as the trust launches a new campaign - Tell Me a Story - which aims to raise awareness of the need for families to support children’s literacy.
To launch the campaign, the trust is calling on families to spend 10 minutes reading with children as part of Family Week Story Time on June2.
The latest findings come amid continuing concerns over the effect of modern technology on young people.
In a study last year, researchers from Monash University, Melbourne, Australia, said mobile phones made youngsters less thoughtful and more prone to making mistakes elsewhere in life.
It will also fuel fears over the state of literacy skills among primary school children in England.
Last year, English exam results for 11-year-olds dropped for the first time since Sats tests were introduced in the mid-90s. Some 80 per cent of pupils in England reached Level 4 - the standard for their age - compared with 81 per cent a year earlier.
A report from the National Literacy Trust said: “Simple interactions, such as being read to, and exposure to books, magazines, newspapers and environmental print, impact children’s progress in learning to read, and children who come from richer home literacy environments show higher levels of reading knowledge and skills at the start of kindergarten and throughout primary school.
“There is also ample evidence that parents who promote reading as a valuable and worthwhile activity have children who are motivated to read for pleasure.
“Involvement with reading activities at home has significant positive influences not only on reading achievement, language comprehension and expressive language skills, but also on pupils’ interest in reading, attitudes towards reading and attentiveness in the classroom.”