Such an interesting idea and amazing execution! But honestly, I don’t really see it as a standalone accessory for Phone (3a) as it is. To me, it could be much more fitting to be a part of Nothing community. Being able to trade your characters, and possibly have them on your profile as avatars, would make community interactions much more unique.
If I would’ve make this idea as an accessory, I would surely take more inspiration from Tamagotchis. Maybe something with a dotted e-ink display, put in a square body that still has nfc capabilities, would really elevate this concept and let it shine to its fullest.
I’m not really a designer (definitely not a great one at that), but I really appreciate the kind words you’ve left on my software concept over here on community. ❤ Absolutely love the care and the attention to detail put in your presentation!