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Originally, we were deciding between a light theme and a dark theme for our color scheme. For the heuristic evaluation, we had submitted a protocol where we used a light theme, with an off-white as the main background for our site. However, as we asked more people for their opinion using our first computer protocol, we found that more people preferred the dark theme. It seemed that since more photos tend to be brighter, there was more contrast in our site if we had a dark theme, with a gray as our main background color. This also brings more emphasis and focus to the photos.
Animating Group Icons
When we first met with our TA with our first computer prototype, our icon for groups was composed of a stack of three photos with the main photo being a photo from the group. Our TA mentioned that this made our site look like a Web 1.0 site, because it wasn't very animated. We also got a comment in our heuristic evaluation stating that the stacks were confusing because wasn't a correlation between the stacks and the number of photos in the group. Thus, we did away with the stacks and decided to animate the group icons, showing multiple pictures from the group when you move your mouse over the icon for a group.
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Originally for our first computer prototype, we had our photo layout in such a way so that the width for both vertical and horizontal photos were the same, meaning the height of vertical photos were much longer. However, we also decided not to add much white space between rows of photos. This meant that some vertical photos would extend into the second and third row of photos, making rows not perfectly aligned when vertical photos were added. We thought there would be an aesthetic appeal to this layout. However, we found in our heuristic evaluation that some people preferred thumbnail sizes that were more similar. It was also brought to our attention that the lack of defined rows made it harder for users to order photos, because it wasn't immediately obvious which photo came before others. We decided that it was still important to distinguish between horizontal and vertical pictures because it created an affordance for recognizing photos quickly. Thus, to keep this and still have defined rows, we decided to create more white space in between our rows of photos and shorten our vertical photos from what we originally had. That is how we ended up up with our final photo layout for groups.
Share Suggestions
One of the highest friction components of our websites was when a user had to enter the emails of the people he/she wanted to share with. The problem with this was that a lot of people had difficulty remembering the emails of their friends. Thus, even though our interface was very simple to use, this still resulted in a lot of errors because the manual typing would have a lot of room for errors. Thus, we created suggestions when the user began typing the emails of friends to share groups with, and these suggestions were based on previous emails that the user had used before. We believed this made the process a lot more user friendly for the user and also reduced the possibility for error. 
Simplification of Comments
For our second computer prototype, we simplified the commenting interface. We had hint text in the comment box that would indicate that comments should be typed there, and we had it so that the submit button would only appear when you clicked in the comment text area. This was so we could have a very minimalistic effect, only having buttons and text when it was necessary to keep things clean.
Implementation
Sharing Groups
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