HealthTap, an online medical question-and-answer service that boasts 10 million active users and a pool of over 60,000 doctors from across the US, yesterday unveiled an updated version of its product. Dubbed Prime, the new service, which is available through the company’s mobile apps and website, lets you text or video conference with a doctor, whatever the hour. The value proposition here is that the service saves you making an appointment with a doctor and traveling to their office for a meeting, which may take 1-2 hours depending upon various factors. With Prime, however, you can get access to a doctor within a few minutes.