— gmail
L=delete by default. I prefer soft-delete i.e. Archive
R=snooze by default. I prefer toggleUnfreshFresh

This toggle has explicit banner announcement.

— BlackBerryEmail .. not configurable
L=Delete etc
R=toggleUnfreshFresh , among others

— SMS
L=markFresh i.e. unread
R=markUnfresh .. the 90% frequent action