Once you've set up Saga and begun your lifelog, the Location Services arrow will always be on in your iOS status bar. The app has three primary tabs -- Lifelog, Now and Me. Lifelog displays a reverse chronological listing of everywhere you've been as well as input from those other connected apps while you were at a location. For example, my current listing shows that I've been at TUAW Denver Office (aka my home) for 13 hours and 27 minutes, and shows a list of tweets, Facebook posts and my weight (courtesy of Withings). I can confirm that I was at that location -- that's one of the few actions that users need to take. Other information can be edited, notes added or photos added at a location.
Tapping "Now" displays where you are at the current time -- hopefully, you already know that -- as well as a total of how many hours you've been running the app. There's a "Snaps" button that, when tapped, gives you an opportunity to take four quickly spaced photos in a photo booth format. Once again, information can be edited, showing that you're either in transit or in reality at another location. In kind of a meta move, you can share your information -- which may include input from those connected services -- on Facebook or Twitter.
Finally, there's the Me tab. That's where the settings are, but more importantly where the "infographs" are viewed. What are infographs? Well, Saga takes your personal data and either displays it in graphic format or compares it with an average of all users. For me, this was the least interesting of the tabs, as the infographs really made no sense. A chart of time spent at the top three categories last week? Well, I spent most of my time in my home office, so there's a huge bar showing that I spent about 140 hours at "Home", with a few hours at a movie theater to see Star Trek Into Darkness and some time at the local community college teaching a class.
One interesting chart showed the distance I traveled each day last week versus the average, but many of the other charts seemed pointless to me. Do I really care about the typical commute-to-work time when I don't commute to work? It seems that there should be some way to turn off some of the infographs in Saga if they're irrelevant.
I found Saga mildly interesting, and to those who are struggling to find a way to capture their every move, it might be the app you're looking for. In the end, I personally decided to remove it from my iPhone and cancel my account. Since I started using Moves (free) as a replacement for a Fitbit Ultra that no longer wants to sync, I pretty much know where I've been and for how long, without the unnecessary fluff of the infographs.