Just FYI, the UUA is in the process of designing a UU app. A couple of weeks ago they put out a page where you can submit ideas. As is often the case, however, I can't find it easily by searching for it through the UUA's page. Problem number one is that "phone" and "app" are too common. "Submit ideas for mobile phone app" doesn't turn it up, either. Fortunately, I have found it for you. It's at http://www.uua.org/about/184350.shtml.
But, if you can't wait to see what the UUA will turn out, the Church of the Larger Fellowship just put out a very nice app, "Quest for Meaning." The Android version is available; the iPhone version may still be "coming soon." It was free when I downloaded it during GA, and features four options -- reading joys and sorrows, posting a joy or sorrow, lighting a chalice (along with a reading), and podcasts. It's a nifty little thing. I found it hard to located. In my apps store, I searched under "Quest" and then under "Unitarian" and then finally found it by searching for either "Quest Unitarian" or "Quest Church of the Larger Fellowship" -- I can't remember which.