HealthVault-Enabled Apps

What is an app?
What kinds of apps are available?
Why do apps need access to my HealthVault information?
Where can I see a list of the apps I have authorized to access my HealthVault record?
How do I remove an app’s access to my HealthVault record?
Why isn’t information I added in my app showing up in my HealthVault record?
Why isn’t information I added in HealthVault showing up in my app?
I’m having trouble with an app. Who should I contact?
If I delete information in my HealthVault record, will it automatically delete from apps I use, too?