When you register your business account on Omnibasis, you choose your business subdomain.
It is you business unique ID on Omnibasis, will produce vanity URL which you can use to login into your site from anywhere.
For example my_company.on.omnibasis.com - unique ID for your business on Omnibasis, subdomain name should start with a letter and continue with letter, underscore, dash or digits (2 chars or more), i.e. my_company. In example above your business subdomain is my_company.
Do not worry, you can always point your site URL later. Learn how to use your own website address on Omnibasis with FREE SSL certificate.