This idea has been merged into another idea. To comment or vote on this idea, please visit APP-I-1593 Edit & change custom field type.
As an admin, I receive requests to change an existing field to a different type of field (ie. single select ddl to a multi-select tag list), but I need to completely delete the field & create a new one. This causes me to lose data + have to update all associated layouts. It would make things more efficient if we could take an existing field & modify it to a different type.