Yeah, it’s not something the Playdate SDK has support for natively (and probably too niche to expect anytime soon). I’m not sure if it’s possible (or feasibile) to implement the TLS stack myself, something I still have to look into.
That being said, most of the client cert features seem to be for writing/posting content, which is not super comfortable from a Playdate to begin with. So probably not super high up on my list right now.
I’ll be honest and say I didn’t expect there to be many “power users” for this app :D