[zhichu]

For a example, if the mobile keyboard can collect the words you type to enhance their dictionaries. Then you will get a better typing experience.

[raxxorraxor]

I don't see how this has to include any personal information. Perhaps a specific set of otherwise rarely used terms might be able to identify you, but there is otherwise no need to attach any PII to these data sets. The trivial case to implement such a growing dictionary would not collect any private information.