From Playdate Community Wiki
Panic have developed 2 official accessories. You may also use a lanyard in the corners of the Playdate itself.
A cute, clean way to protect your Playdate. The Playdate Cover aligns with Playdate's screws and secures itself magnetically. Plus, when folded, it looks like a delicious electronic ice cream sandwich.
Playdate Stereo Dock
The Playdate Stereo Dock is a stereo Bluetooth® speaker charges your Playdate, holds your pen and looks great on your desk.