Can I add a customer's purchase order to an invoice created on my phone?

Hello, Bill-C. Currently, we do not have an option for the purchase order number to automatically reflect on a customer invoice. 

We can only utilize the Custom field feature to add a Purchase Order number on the customer invoice. Here's how create one:

1. From the Home page, click Settings (gear icon) in the upper-right corner and select Custom fields under LISTS.
2. Click Add field and start setting up the custom field for the purchase order number.
3. Mark the Invoice box under Select forms and toggle on the Print on form.
4. Click Save.

Then, go back to your invoice and enter the purchase order number manually in the custom field (PO Number). You can refer to the screenshot below.

I acknowledge that having this kind of automation would help streamline your workflow. For this reason, I recommend sharing your suggestion with our product engineers.

1. From the Invoice page, select Feedback. 
2. Please provide your input in the designated box.
3. Click Submit feedback.

Please let us know if you have other concerns. We're always here to help.