Yes, the UKKO Entrepreneur service includes a client register as well as a product register. You can save your client information easily to the client register, which makes it easier to add a client on an invoice when creating one.
You can also save products and services in the product register. When creating an invoice, you can simply choose the correct service or product from the register, making the process of sending an invoice quicker.
You can find the client and product register from your own profile under "Customers" and under "Products".