Imagine a service which is called "Add a cat or a dog to that" (https://developers.google.com/glass/stories)
What is the best practice to do that:
Add two contact "Add a cat to that" or "Add a dog to that" to the user
Add one concat and when a user share a photo with this contact, insert a new item in the timeline and asking to choose between adding a dog or a cat to this photo
Thank you!