The Activity stream for a Mobile form is not displaying all the expected field changes.
All Mobile Releases
On Mobile the activity stream by default will display all the field changes which the user has access to and are added on the activities filtered setting.
The fields displayed can not be changed or customized from the mobile view.
Things to Check:
If all above steps are reviewed, then the issue may be due to the table specific Activities (filtered) configuration.
Verify the expected fields are all added to the activities stream by checking and updating the 'glide.ui.table_name_activity.fields' system property.
Additional links for reference: