What is Somleng?
Somleng is an Open Source implementation of Twilio. Although Somleng currently only supports a subset of the features that Twilio supports it can be used in many cases as a drop-in replacement for Twilio.
How does it work?
Somleng's Twilreapi (Twilio REST API) is an Open Source implementation of Twilio's REST API. Although Twilreapi currently only supports a subset of Twilio's API endpoints, the endpoint that it does support are almost identical to the ones implemented by Twilio's REST API.
Why would I want to use Somleng instead of Twilio?
Please see Somleng vs Twilio Comparison for a detailed comparision of Twilio vs Somleng and reasons why you may or may not want to choose Somleng instead of Twilio.