American Well, a telehealth company, has developed a comprehensive online consult system that allows physicians to chat via Web video, review a patient's record, write a prescription, and make a referral. The company business model involves partnering with payers to set reimbursement rates for online consults. Doctors who choose to work with American Well can sign on whenever they want and see patients who are looking for an online visit. The company recently announced its first big customer: HMSA, Hawaii's Blue Cross Blue Shield provider, which has just under a million members and is the state's biggest insurer.