If you want to know where your child is at all times, you should get a GPS tracker. You can get portable GPS trackers to track a certain brand of cell phone or even a tracker watch. You may find they use GPS to follow those that need to be tracked at all times. The one thing you should know about GPS trackers is to find the type that does not allow others to track you. Choosing the right GPS can be a key to knowing where a loved one is and where to go when driving.