According to a bot on Twitter, the least used emojis are the following: the blue ABCD box and the aerial tramway emojis. This of course has led to a war on Twitter with users voting for which one of these least used emojis they're rooting for.
As for the most used emojis? According to Lifewire, the most popular one is the laughing crying face. There's even a program that tracks emoji usage in real time. What a time to be alive!
Here are some more emojis that get almost no usage!