I really liked this. I had fun exploring the phone before actually playing the game, and ended up shutting down the phone. I'm guessing this usually closes an exe? But since its on web I just reloaded the page. I think it would be really funny if turning off the phone was an ending, like "you were too scared and chickened out" lmao.
Besides yapping about how much I liked the interface, the gameplay was good too! More stressful than spooky, but I tried to get the highest score I could (I think 11k?). My first thought was "dang this guy poops a lot" LOL. If you choose to expand this, I would think about lowering the difficulty (play sessions were really short) and maybe making the ghosts more visible. If I didn't read the phone instructions I don't think I would have noticed them without looking hard.
Overall I think you nailed the style, especially the tamagotchi inspiration (I'm assuming). Great submission!