One of the cool new features of iOS 10 is the ability to input Emojis through the predictive row at the top of the keyboard that tries to guess what you're trying to say before you say it.
When you express certain words, iOS 10 will recommend Emojis to communicate the word instead, and a new free jailbreak tweak called EmojiSuggest brings this functionality to jailbroken iOS 9 devices as well.