Check out MS Health Vault to keep track of personal health info. Also St.John Cymru-Wales app. Not sure about other apps, I usually browse their mobile sites
Lexi Comp does not have an app, so if you are a medical professional windows phone is still a no go. I had to switch to iphone because of the lack of medical apps for WP.
I signed into Epocrates on my browser book marked and pinned it to my start screen. No way in the world I'm going to stay with iPhone only for Epocrates.
While these may be fine for lay consumers, they aren't the sort of professional grade applications that doctors and nurses need.
I'm very glad to see Up To Date on the platform.
The absence of Epocrates is disappointing, but is somewhat alleviated by MPR.
Still there are tons of iPhone apps (and even android) that aren't available (ATLS, Mescape, Pepid, Medical Calculators, PediSafe)...
It would be really nice to see Microsoft make a big push to get some of these apps on Windows / Windows phone as the Surface Pro with Citrix is really well positioned to be the only acceptable portable device you can use to effectively interact with modern EHRs. iPads and Android tablets (partly due to the lack of development of effective dedicated apps by EHR companies, partly becuase of their lack of horsepower to handle the task through Citrix) aren't good choices.