You can convert an estimate to an Invoice in Moon Invoice easily by following the steps below.

1. Open the Moon Invoice application on your device or tap on this link.
2. From the main menu on your left, go to Sales ➜ Estimates.
3. Open the existing estimate, then click the three-dot icon (⋮) on the right-hand side and select Convert to Invoice.
4. The estimate will now be marked as Invoiced.