http://iscoresports.com/

When a batter gets a base hit, I type 'In Play' => 'Single' => Tap Location Where Ball Hit => Safe => First

Assuming he stays at first, do I select 'Held up' or 'Advanced by Batter'? I assume Held Up, since Advanced by Batter has to do with someone already on base at the moment of the hit.

Thank you.

Yes, Held Up is the right thing to press. It does not hurt to use Advanced by Batter, but Held Up is more appropriate in this case.