What often happens is the pitcher is batting and no one is on base. You want to have the Courtesy Runner ready to go with a helmet on (rather than fixing her hair and gossiping in the corner - not that that would ever happen). With no runner on base, there's nothing to tap to see who the Last Out was. When using an iPhone for scoring, it's inconvenient to have to open the scorecard on the small screen and search for the last out while action is happening on the field. I usually tap the "Ball" button four times and put the pitcher on base, tap the runner icon, get the last out, then undo four times.
If there were a way to do that with no one on, it would be incredible! Maybe a finger slide up on the batter icon or something like that?
http://iscoresports.com/
Customer support forum for the iScore Sports line of scorekeeping products