in Approved Service Providers >ringto will go to https://www.obitalk.com/info/products
https://www.obitalk.com/obinet/pg/services/itsp?i=ringto&d=74883
wil be This device does not qualify for RingTo
help
When was your OBi100 purchased? If it was before 5-1-14 you're out of luck.
Ring.To has been pretty clear about this from the start.
QuoteOnly devices purchased after May 1, 2014 are eligible for RingTo service. The following Obi models are supported with RingTo:
https://community.ring.to/docs/DOC-1029 (https://community.ring.to/docs/DOC-1029)