In case you don't want to use your own mail app, you can use our mail server.
Navigate to ⚙️Settings - Client communication - Email Settings - and turn off "Send with iOS mail" or "Send with mail app"
How it works
Emails will be delivered to your customers from an email address invoices@mail.billdu.com with your business name displayed in front.
Replies will be routed to the email address of your account.