I have been working on this for a while now, but I am still struggling to wrap my head around it. I am using Drupal 7.x with Views, Rules, Views Rules, Twilio and Services to try and achieve this.
Here is what I have so far:
User submits a node with only a few of the many fields filled. On submit, Rules schedules the following action set.
Views Rules, contextually filtered by uid and content-type, produces the user's mobile number and the first field of the node that has a null value.
An SMS is sent via Twilio to that user's mobile number containing the value of the field's label (which is a question).
Here is where I am stuck. I would like the SMS reply from the user to update the value of that field, thus saving the answer to that question in the original node authored by that user.
How would I match the response to the user, node and field and update that field's data with the SMS reply?