One of the first applications I did for Android was a very simple application which simply takes a picture using Camera and then send it to a remote server. Very simple, but it introduced to me into the android world and the notion of activities and communication between different applications.
A little addition to this application I wanted to make was the possibility to share any of the pictures already taken. To do that I wanted to add the application to the list of the choices which appear when an user click on the “share” button when view an image using the default Gallery application.