What does the Cell Network Search do on the iPhone 4s?

Question

What may happen if I turn Cell Network Search off on my iPhone 4s. It's under location services scroll all the way down to system services. Will I not be able make or receive calls?

Answer 1

Yes, go ahead and turn it off.  It SENDS location based information to Apple for their use (marketing, trouble shooting, who knows all or what).  Basically it records the tower ID of the towers within range of your phone as you move around throught the day and sends that back to Apple.  Since the location of the towers is known, they then get information about where people are most using iPhones during the day, what the loads in different areas are, and other stuff that lets them learn about how and where iPhones are being used.
It has NOTHING to do with how your iPhone actually functions normally, so you can disable all of the services listed there ifyou wish.
Compass calibration MAY be useful in some cases - I know when I was trying Waze, it often could not get a reliable position fix until I re-enabled compass calibration.  I don't know why that was, as all I know about compass calibration is it supposedly allows for a more accurate correction between geographic and magnetic north.  But at least with Waze, it clearly assisted Waze in getting and holding a location fix when driving, in areas and at times when without it on, Waze was unable to track my movement, or sometimes even get a fix at all.
Setting time zone - IF you were traveling across time zones, and were out of range of a cell tower (so no cell signal to correct your clock) or your clock failed to change correctly once you had cell signal again, then turning this on may help correct the clock.  Note that from posts here, usually you just need turn it on, let the clock correct itself, and then can turn it off and the clock will be fine (it just helps when you've shifted multiple time zones with no cell signal for the phone to correct itself by during the journey).
The other four in that list, I have never enabled as you just don't need them for anything, and they do use power every time they use location services and everytime they send data.