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.
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.
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.