When you post to a Social Feed, News Feed or Crowd Pics type page, your post is attributed to whatever name you used to add the app.

If you're an app creator:

Log in to the app with your account. Whatever photo is set to your account at http://yapp.us will show up when you post.

If you're an app user:

Log in to the app by going to the person icon and entering your email/ password or connecting with Facebook.  Then tap "Edit" and tap "tap to change photo."  Add a photo from your camera roll or by taking a selfie.

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