Almost all mobile devices sold in the UK operate on either iOS or Android, with Apple and Google holding exclusive or leading positions in their app stores and browsers.

Apple Inc. and Alphabet Inc. were hit with UK antitrust investigations over concerns their dominance in mobile services is distorting the market and putting up barriers to entry for competitors.

Britain's competition regulator launched an investigation into Apple and Google's mobile ecosystems to assess whether they're in breach of strict new tech laws.