Tap on the 3 lined button in the top left of the screen inside PrintCentral Pro to open the side menu. Then tap on 'Contacts' to show the contacts screen.
Contacts can be selected from your contact list using the checkbox on the left of the contact name. Use the ✓ tick button at the top of the screen to select all Contacts. Once you have selected your contacts, tap on the Print button.

You can view contacts in each of your contact groups group with the group button in the top tool bar.
After you tap on the print button, tap on "Printer Options" and then tap on "Contact layout" to choose a different print layout.

You can use the search button to enter some text in the search field to filter the list of contacts you want to see.

See the section about contact access if you do not see your contacts. View