Agree with the important person for you in advance that if necessary, you can determine its location. Then install it on the phone one of the programs that lets you know where the phone GPS. Such applications are called trackers and you can find them on the Internet, as well as special services applications for various mobile platforms, for example, OsMoDroid or Family GPS Tracker for Android GPS Tracker for iOS, etc.
Install the software on your phone and the phone of the desired subscriber. Configure the application accordingly. Now you can absolutely free to learn where the phone correct number by sending the request through the app. Remember that the Internet also has many fraudulent resources offers a to determine the location of the subscriber free of charge or for a nominal sum. It is better to avoid them and to use proven methods.
Note the official services to determine the location of the subscriber, from the mobile operators. The price for using it is quite low, so these options can be called shareware. For example, in MTS there is a service Locator that allows you to know the location of the phone and its owner. Send to 6677 message with the number of the person you want to find. Also activate the "Locator" on the site mpoisk.ru.
Subscribers of Beeline can send an sms with the letter L to the number 684. The query cost is 2 rubles. To determine where the subscriber is operator MegaFon in two ways, which are available in various rates. For example, a special service of search of phone your child can activate by dialing *141#. An alternative option would be option a Locator, which connects to the operator's website. Simply fill out the application and send the operator the Megaphone, then your number will receive the coordinates of the desired subscriber. A complete list of available services can be found on the website of the operator the Megaphone.