Using fakesms service in Functional Test Automation

How do you automate OTP related test scenarios? Do you use a fake SMS service? Does it have restapi to query the SMS messages? geography support? 

To clarify - this needs to be done as part of my functional test automation, where,

• the test could be running against a browser, where the browser does not have access to the phone, or,
• the test could be running against a real mobile device (without SIM), so no way to receive the SMS, or,
  
• the test could be running against an emulator (no SIM), so no way to receive the SMS

Scenarios include: login, payment, SMS content 

Hence I am thinking about using a fakesms service which has API access capabilities to retrieve the SMS. This will help when running automation on browser or devices / emulators without SIM.

Note:

• There is no access to DB or API to query the OTP. 
• I don't mind using a paid service

 

Thanks in advance for your help!