A 5.3mm (0.2in) thick 4G phone has been announced by Japan’s biggest telecoms firm NTT Docomo.
The compact device, which will be released in Japan next month, is designed to fit inside a card holder.
It is part of a trend to offer so-called companion mobile devices to those who already own larger smartphones.
The phone weighs 47g (1.6oz) and features an electronic-paper touchscreen, similar to e-books.
