Just had this recommended to me (after just getting a smartphone) and it is awesome. One feature request would be the ability to set an alarm for certain logs.
An example would be if you want to track your pulse throughout the day but don't want to keep having to remember to do it. You might set an alarm to go off on an interval so that it just prompts you to enter a number every so often as a pop up.
I realize that I could just set an alarm on the phone as a reminder to update the log, but the difference between having to open the tracker, select the correct log, and then enter in the number vs just having a prompt pop up asking for a number might mean the difference between just ignoring the alarm and actually putting in a number.
I'm coming and might be bringing a friend.