No it is not a coldcard.
But it does have a se like a mk series coldcard.
You could be we it as a type of signing device/hhw.
This thing will do all sorts of shit.
It’s a diy device.
Yes you can probably use it as a p2p messaging device (similar to armachat).
Browse nostr not sure really but you could use it to post notes on nostr.
Have you listened to