From the bottom row select the Clients icon

Tap on + in the upper right corner

Enter all necessary details such as Client name, email, country, address, contact, tax number etc. Company IDs will change according to the selected country. You can also edit the company VAT/TAX IDs by yourself

To add a client from your phone, select Choose from contacts. Your device may ask for enabling access to your contacts - select Yes. Now you can select a contact from your contact list - it will try to import all necessary data

Enter an e-mail address for convenient invoice sending. When you send an invoice, cash receipt or reminder, this email appears in the email field automatically

You can also change the Identificators (Company No, VAT no) if needed

Enter Shipping address below if needed, it appears on the invoice as well

Click Save