Even if you don't use Shuangpin officially, most Chinese input methods supports a similar feature (简拼) for popular phrases, where you type first English character of each word to type out a phrase of several words.
For example, to type "thank you" in Chinese (xiexie), you just type "xx" and it should automatically give you "xiexie" (Chinese characters) in most popular Chinese input methods.
Chinese language has this feature "built-in".
It is officially called 双拼 （Shuangpin）where you type two (English) characters of each word to type out the entire word:
https://zh.wikipedia.org/zh-sg/%E5%8F%8C%E6%8B%BC
Even if you don't use Shuangpin officially, most Chinese input methods supports a similar feature (简拼) for popular phrases, where you type first English character of each word to type out a phrase of several words.
For example, to type "thank you" in Chinese (xiexie), you just type "xx" and it should automatically give you "xiexie" (Chinese characters) in most popular Chinese input methods.