Many mobile apps request too many permissions and don't explain how they collect users' personal information, a study of 1,211 popular apps by the Global Privacy Enforcement Network has found. The majority of the apps reviewed did not adequately explain to users how they were collecting and using information, according to the study, carried out by 26 privacy enforcement authorities in 19 countries. It also found that a third of the tested mobile applications requested excessive permissions that were outside the scope of their functionality.