So far, the scientific evidence shows it is unlikely that mobile phones could increase the risk of brain tumours, or any other type of cancer. But we do not know enough to completely rule out a risk.
In 2011, the International Agency for Research on Cancer classified mobile phones for the first time in their 'gold-standard' rating system. They said the devices could 'possibly' cause cancer in humans (group 2B), but there wasn't enough evidence to come to a clear conclusion. Read what we said at the time on our Science Update Blog.