Pros
In my opinion, pMD has some of the best aspects of a large company (profitable, stable, large user base of happy customers, existing products that are proven) and a small company (exciting ideas, small tight-knit team, fast moving, fun culture). Speaking to my experience as a developer here, it's incredible to have so much close customer contact and to be able to make a difference in the lives of busy doctors who really need the help. To me, that's how you know your work is worthwhile - you hear firsthand from real people whose lives you're improving. It's also been helpful for me to learn mobile software development at a company which has been doing it for more than 10 years. This is a company where mobile is part of the DNA and that definitely knows how to ship fantastic native apps for all kinds of mobile devices. There are fun, meaty technical challenges to make software that runs incredibly fast on a mobile device, even when it deals with sensitive data that must be encrypted.
Cons
I love the company a lot and I've been here since 2007, so I have to dig a bit to think of any major cons. I would say that there can be a lot of travel to customer sites since we have a very in-person culture. If you're the kind of developer who rarely wants to see or interact with your customers, that would get tiresome. I find it energizing to get face time with our customers who are on the cutting edge of healthcare and whose ideas help to guide our product development. But it's not for everyone. Also, the company is located in the Presidio in San Francisco, so it would be hard to get to the office if you live way out in the East Bay or South Bay.