A new Japanese law is going into effect that could loosen the dominance of tech giants over smartphone services. It aims to bring users greater choice for app stores and more.

Starting December 18, firms like Apple and Google will be prohibited from blocking third party app stores on iPhone and Android devices.

The law also aims to loosen their grip on web browsers and search. The firms will now be required to give first-time users multiple choices for default services. This also applies when people update their operating system.

The Fair Trade Commission says the changes will improve convenience by encouraging new market entrants.

But some public comments released by the commission expressed concern that the legislation could undermine user security.