For the current applications of iPhone, iPad and Android phones and tablets each time you "Update Cards" always all data of all of your lists is synchronized with the phone.
On the phone you can very comfortably decide what lists to study with.
Just a small comment: Users with very old applications (which do not show lists on the phone) and users using Desktop or Java applications do not have lists on the phone. In that cases the priority to fill in data on the phone is based on how "Old" that data is, with oldest data having priority.