Creating an invoice was never easier! With the 'plain' template you can invoice pretty much everything. With the 'Project-Expert' template you can generate invoices per project & expert. You can even send out the invoice via email, directly from ZEIT.IO. No need to download the invoice as PDF and to use a seperate email client to do the job!
Of course you can sort and filter the invoices by different criteria. And if you wish you can cancel already finished invoices with one click.