The iPad Hike POS Register app can print from Enter Sale and Sales History - all Point of Sale tasks. This will allow you to print receipts from current and existing sales to the linked thermal receipt printer that is connected to the iPad.
PLEASE NOTE: The iPad app can not print any of the Reporting/Administration/Back Office reports. While you can access and view these reports from the iPad app via the 'Admin' tab, the iPad app does not allow printing functionality as these reports are designed to exported into spreadsheets for printing and will not print correctly using the connected thermal receipt printer for the iPad app.