On our templates, the document number (invoice number, delivery note number etc) all use the EposNow transaction ID as this is unique in EposNow and does not change.
However, this is not always sequential so if you wanted sequential number, you can use the
EposNow Ticket Numbering app which is available for free on their App Store. On your order template, you can then use the
Order Ticket Number EposNow field to use this ticket number instead.