Following the Dublin Bet game, Nintendo Miitomo Mobile game just got a huge update that lets you send DMs, decorate your room, and use multiple miis. You can now add wallpaper and flooring to your room on Miitomo.
There’s also a new feature called Sidekick Miis which lets you use other Miis you have created – and decorate their rooms as well.
You can add “Posters” to your room – and possibly furnishings too (haven’t finished exploring everything yet myself). The Posters can be miifotos, or any photo saved to your mobile device. I chose one of my cats to use as my poster.