After you installed mobile application you’ll need to create an account (if it wasn't created in Web Dashboard).
Launch the application
Tap Sign Up button
Confirm if you are agree with them
Select Client or Partner Sign Up option and follow account creation procedure
Client Sign Up – for personal or small company use, Developer's clients and tests
Partner Sign Up – for Distributors, Retailers, or Contractors who need extended own and client's Organizations management functionality available in Partner Mode.