Hi Scott,
The Windows Store app allows you to define the sharing function with two contracts:
The sharing source contract
The sharing target contract
#Sharing and receiving content (Windows Store apps using JavaScript and HTML) (Windows)
http://msdn.microsoft.com/en-us/library/windows/apps/Hh758314.aspx
In your case, your app is going to share data to other app, then you need to implement the sharing source contract and supply the data to share (the formats you want to support in your app) as you've already done. However, whether other application will
accept data (or accept what kinds of data) from your app (or other app which also supply data to share) depends on the developer of that app. In this case, you cannot control the sharing target behavior of the "People" application.
You can download the "sharing source" sample and try share various data and watch how "People" app will show in the target app list (when you change the data type to share):
#Sharing content source app sample
http://code.msdn.microsoft.com/windowsapps/Sharing-Content-Source-App-d9bffd84
based on my test, the "People" app will appear when I choose to share "link" or "html" data. But when I actually click the "People" app, it says it failed to get the share data. And that's the behavior on my local
test machine and it is totally depending on the People app's implementation.
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