The use of mobile phones by children has in recent years been increasing, the onset starting earlier and earlier. This has led to concern about whether children might be at higher risk and whether mobile phone use should even be forbidden. Advice from highly reputed committees on both national and international levels is contradictory and on the whole more confusing than helpful to worried parents and physicians, but this can be explained. It is shown here that different opinions derived from the same database reflect the different way in which uncertainty of knowledge is dealt with. Based on the assessments of the international committee and established knowledge on children's development it can be concluded that existing exposure limits do in fact provide reasonable safety. Compared to adults, however, children do in fact need to be considered at a relatively higher potential risk, depending on their phase of development. If adults are advised to minimise their exposure, this is even more justified for children. However, circular reasoning must be avoided: the uncertainty-triggered application of precaution must not be misinterpreted as evidence for definite risk.