Today, just as I woke up I opened the Facebook app on my phone. My cousin had uploaded some pictures of her recent trip and I decided to browse through them. As I was browsing, I got confused about the gesture to see the next photo.

Let me explain this.So as you might know, Facebook mobile app has two modes to browse through photos. If someone has uploaded a large number of pictures and you click on one of them. You enter the first mode, which is a vertical list of pictures with footer for “comments and likes” for each picture. When you further click on the picture, a larger view(second mode) of that photo opens up. Now, to see the next photo you have to scroll through the pictures horizontally. In my half sleepy state, I got confused about how to scroll through these enlarged photos-(vertically or horizontally ?). This was because, somewhere in my unconscious mind I had learned that vertical and horizontal scroll both work for Facebook photos. I had never acknowledged the fact that there are two gestures for different scenarios. Now should I remember that vertical scroll works for the zoomed-out version and horizontal scroll for zoomed-in version of the photos?

I think this is a bad design. I am not sure if having both-vertical and horizontal scroll on the same app within the same feature is a right thing to do. All I know is as a user of Facebook app, I woke up to confusion !

Maybe Facebook should have only one type of scrolling or maybe the gesture can be clued. If user testing, approves of combining two types of scroll(fb must have done user testing for this) within the same feature then ambiguity can be removed, just by using an arrow to indicate horizontal scrolling.

P.s. Maybe this happened to me because I was half sleepy. But accessing Facebook as soon as you wake up is a common habit nowadays. Maybe other users also get confused. If nothing else, its a usability issue and it deserves to be considered and user tested.