4×A53 @2.0GHz The Gemini PDA is a personal digital assistant[1] designed by Planet Computers[2] in association with Martin Riddiford, who formerly worked on the Psion Series 5 in the 1990s,[3] and crowdfunded via Indiegogo in 2017.

[4] The Gemini bucks the trend of modern smartphones in its screen being primarily used in landscape aspect, and having a keyboard, i.e. taking on the form of a subnotebook.

Planet supports running two operating systems on the device, and it dual-boots between Android and Linux.

Some early devices were made with the X25 SoC as specified in the Indiegogo campaign, with the factory switching to X27 as stocks of the older X25 were depleted.

The original Indiegogo campaign allowed backers to pay extra for various accessories and features: Planet Computers announced successor models to the Gemini called Cosmo Communicator and Astro Slide 5G Transformer.