Here is my second recommendation and it is an unusual App in many ways but it is often useful and is a must for students. It is called TimeBook and it is a kind of sophisticated stop watch. Here is what you do:
Activity Pattern - the idea is that you tell it all (or some) of the things you do: reading, praying, working on assignments, learning to play the trumpet, recreation, eating, sleeping, etc.
Load - Then what you do is load the App and select the category of work and press record and it will keep recording how much time you have spent on a given activity until you pause it. It will keep recording even if you load another App so it never stops you using the Iphone or Itouch.
Interrogate - it to find out how much of your time was usefully employed and it does this by showing you charts and percentages. Often it is quite shocking to see how much time you waste or spend on some activities so I would recommend you get into the habit of using it and keep using it for a few weeks just to see how much you work and what that pattern of work is.
Use - What you do with that data when you get it is all down to your own perceptions, conscience and honesty!