XXさんが「いいね！」と言っています。

Well i found it a cute translation of that likes! thing which i never use anyway

Maybe mixxi already has a similar thing? or were the translators having some fun with this app

Is it an app? If it is, I installed it without realizing!

Either way, I think that いいね is generally a lot better in that situation that 好き or something similar haha

yes, 好き（すき）is always getting me into trouble. I am never quite sure how to expressing liking of a non-romantic nature towards people. いいね　is about as good as it gets.