Analogue have announced the Pocket. It's definitely something to get for your retro gaming! You will need to get an additional adapter for Atari Lynx cartridges though. Check out what they had to say -
A multi-video-game-system portable handheld. A digital audio workstation with a built-in synthesizer and sequencer. A tribute to portable gaming. Out of the box, Pocket is compatible with the 2,780+ Game Boy, Game Boy Color & Game Boy Advance game cartridge library. Pocket works with cartridge adapters for other handheld systems, too. Like Game Gear. Neo Geo Pocket Color. Atari Lynx & more. Completely engineered in two FPGAs. No emulation.