Thank you for specifying the device you're using and outlining your invoice concern, info2289. Let's review your default template to ensure the invoice number shows when previewed or emailed.

We can start by logging in to your QuickBooks account through your mobile web browser, then enabling a few fields to display the invoice number in the sales form. Here's how to do that:

1. Go to this link to log in to your QuickBooks account.
2. Navigate to the Gear icon and select Custom form styles under the Your Company column.
3. Locate the default invoice template and click Edit.
4. On the Content tab, select the Header.
5. Scroll down to the Form section, then tick the Form numbers and User custom transaction numbers checkbox.
6. Click Done.
   

After that, you can create and send an invoice in QuickBooks on the go.

It's also worth noting that you can customise invoices, estimates, and sales receipts to tailor the template according to your needs.

You can add a response below if you have follow-up concerns regarding invoices or inquiries about any other sales forms that come to mind. We'll be delighted to address them.