Sub App and SubDomain

Questions
1

Hi folks,

I am developing a SAAS application using bubble.io.
Can any one guide me how can I create SubApp of my main App ??

Requirment,

  1. I want to keep separate Database for all these SubApplication.
  2. Each Application will be running on separate SubDomain.
  3. On Signup, Bubble workflow must create a new SubDomain and should run new application on subdomain instantly.

Regards,
Poonam.