Sentence autocomplete is a great tool for improving your writing. Whenever the autocomplete is right, start over. You were about to say something so predictable it had little information value.
This is somewhat related to my idea to a machine learning tool, but still very different.
Information is surprise. If the person you are writing to knows what you are telling them, they will not get any new information. If someone, even a machine, can predict what you are going to tell them, they will not get any new information.