PhotoChooserTask has built-in crop option for Windows Phone 8.1
Unfortunately the Windows Phone 8.1 SDK doesn't have this operation and I swear I've tried looking everywhere for it, and the MDSN people tell me it's impossible .... But you can try two options:
First: in the FileOpenPicker workflow, the user has two options: the image file already exists, or it accepts a new image, as shown below:
So, in this case you are not doing anything or talking to the UX area, which is not possible =).
Second: you can create a module (separate project) in the same Project Solution that uses the Windows Phone 8.0 SDK (instead of 8.1). Do what you need to get the job done with PhotoChooserTask ... After in the main project add a link to it and be happy.
Some large projects are using this solution because the 8.1 SDK removed many of the 8.0 SDK's features and did some things that are difficult to do.
One project you should look at in source code, https://telegram.org/apps
Hope this helps.
Good luck!
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