How is mobile technology influencing human behavior and changing societies? In Japan and China, there is a real sense of an increasing generation gap. In China, it is very marked because they have vast numbers of only children moving from the countryside to the cities. In many aspects they lack the traditional family structure, so it is important to use the mobile phone to keep in touch with the family they do have. In Japan, the more contacts people have in their phones, the looser those relationships are. People even 10 years older remember having fewer friends but stronger friendships.

Why has the mobile phone taken off? This is a period of unprecedented mobility. People are moving more–whether it’s to commute, or as refugees or migrants to the cities. The mobile is answering the demands this mobility throws up.

What surprised you most in your research? Going to places that didn’t already have telephones and the Internet and then seeing the enormous impact the recent acquisition of a mobile phone could have. In Dubai, mobile phones haven’t made an enormous difference to wealthy property owners, but they have to the porters who work around the harbor or to traders on wooden ships going between east Africa and the Middle East. Traders, for instance, can now find out about shipping news and who’s selling what to whom.

How has text messaging affected the use of language? There’s an incredible collision going on. It’s almost like kids are choosing from a menu of languages and picking the most efficient way to express themselves. In Birmingham, kids use a bit of Afro-Caribbean with a bit of Urdu or Punjabi, a bit of Arabic, a bit of English.

What are mobiles doing to people’s thumbs? Kids have started to use their thumbs instead of index fingers for other things like ringing doorbells and pointing. In Japan, people talk about the under-20s as the thumb generation.