There are apps you do not need here.
How to delete these in sandbox?
Login your RingCentral Dev portal and click the Organization option. You will see a list of developers. click the pen icon to edit. Now that you are a Developer Admin, you can change role for other as well. The super admin you mentioned probably the role in the service web (sandbox account setup) not the dev portal
Using the RingCentral Phone for Desktop, you can dial or receive test calls, send and receive test SMS or Fax messages in your sandbox environment.
Download RingCentral Phone for Desktop:
Tip: switch to the "sandbox mode" before logging in the app:
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