(Update 02-06-2014) My UP band died. I fully charged it, tried both soft reset and hard reset, as discussed below, but seems could not revive it.
The following was written on Nov. 14, 2013. I have a bit more experience with UP band since then, note Jawbone also came up with new UP 24, which has bluetooth connectivity with the smartphone. Also, Fitbit released the app for iPhone 5s which has the basic pedometer functionalities, I just started using it and so far so good.
Does the job, record walking steps and sleeping time
Need to reboot the iPad sometimes to get sync
The corrosion, partially my dumb mistake
The switch from “sleep” to “walk” is automatically most of the time. but not the other way around. Occasionally I saw the UP band flashes (both sleep and walk indicators), or would not sync. There is this soft-reset, and I found turn off iPad (iPhone) and turn it back on solves most sync issue.