In this module we asked to explore using Picasa to share photos/images. Initially I uploaded photos using Google's Photo app - before trying the Picasa app. Honestly, although I found that Picasa has more options, the Photos app as part of the Google suite of tools was much easier and straightforward, not requiring me to install anything else.
Having the photos online allows me to visually reflect on a learning activity from a class - in the particular example I uploaded for this module, I am able to see examples of student conceptions regarding the model of the atom. It allows me to work out what I could change for next time. For this particular activity I was happy with what my students developed in small teams - it accurately reflected the model I wanted them to understand.
More powerfully, publishing online allows a user to share photos with a colleague and allows for external contributions, rather than leaving things in just the one classroom/professional learning team.