What storage data does keyboard apps on Android accumulate? On my Android phone I have installed the Gboard keyboard. After some small use, I see that it has accumulated 20 MB of data!
Why can a keyboard app accumulate 20MB of data?
Keep in mind that GBoard provides a lot of language specific functionalities like automatic word correction or offline speech recognition.
It seems like GBoard downloads these language specific data on first use. For example the directory com.google.android.inputmethod.latin/files/superpacks/delight seems to contain the offline language specific speech recognition data file(s).
Therefore a user data of 20MB seems to be reasonable even if GBoard has not been used for a long time. Most of this storage space seems to be occupied by language specific downloaded data.