Not possible.
yes
Yes it is possible to track or monitor an iPhone without jail breaking. You need to loacte iOS Deployment in your device to eanble this feature.
No. You can download the FindFriend which may be compatible with Android and iOS. If you desire to track the non-iPhone, you should make sure that the non-iPhone and you open this app at the same time.
You have to put a small tacking chip in the sim card and download an app on your 4s to track it
You, as an individual, are not provided the means to track a phone by number, nor are you going to be. If you share a phone plan, and have iPhones, the "Find My iPhone" app can be used. Otherwise, you'll have to do without.
Well you can only track iPhones and you use find my iPhone.
Depends how broken it is.
yes you can, well at least i know you can track an iphone
If you never enabled Find My Iphone and want to try to track your iphone using IMEI number this website can do that: iphonetrace.
Sadly, no. It has to be on.
Weight Watchers has an iPhone app that allows you to track your weight loss, food eaten and exercise. It can be helpful to keeping you on track.