"Miss & Hate" was a simple app I created on Facebook 10 years ago. It was initially a Chinese app, where the "miss" (想念) as in "I miss you," and the "hate" (討厭) as saying "hate you" in a sweet but sarcastic way. Of course, these words rhyme better in Chinese, but you get the idea.
The app was very simple. It allows any user to upload an image and then send it as a "miss" or "hate" message. It has become a sweet way for lovers or friends to express their affection with humor. If a user is in the mood for being sweet, they may send a "miss" to let the recipient know they were missed or express the "I hate you for not messaging me first" kind of teaser message. They can send the images uploaded by other users, too.
Over the years, there have been many cute, fun, and creative images uploaded by users. I just checked these apps on Facebook, and they still exist in my developer account, but I shut down the servers many years ago.
While the "hate" in this app was contrary to what the word means, IRL, there are "haters" who hate us, and we might hate those who have wronged us, too. It's easy to get bothered by these emotions, which brings a lot of negative energy and emotions. Dwelling on this kind of negativity drains our energy. Try to focus more on the people who love you, cos they deserve your love and attention way more than the haters.