Once you've produced your quote and synced your device, you will be able to go into your 'Existing Certificates & Drafts' and then 'Existing Quotes', from which you will be able to see any quotes that have recently been produced on the device.
Quotes that are marked in red, indicate that they are still in draft format, and will not yet be available to be converted into an invoice. They need to be issued.
Quotes that are marked in black, indicates that they have been issued, and the option to convert to an invoice is available.
Once you've tapped on the quote you wish to convert, a dialogue box will appear with a number of options such as 'Open', which will open a copy of the PDF on the device, 'Share', which will allow the user to share a copy of the PDF via either email or another service available on the device, 'Delete', which will delete the quote from both the device and the system, and finally the 'Convert to Invoice' option which will produce an invoice from the quote.
After tapping the 'Convert to Invoice' option on the device, the app will take you to a new screen allowing you to change any details of the new invoice before issuing it. Once completed, reminders will cease for the quote and an invoice will be produced for the same job that the quote exists under.