Smartphones which have a lot of characteristics appear recently and that enable them to compete or replace the computer most of the time specially in dealing which internet and services they require high potentials (processing, memory .. ect) and modern technologies in specific and we must not forget to mention that smart device have other potentials, like dealing with Wi-Fi, GPS, GPRS/3G and the programs which increase the willingness and desire to have them by all. While dealing with GPS in high places, metro or open area which has a thick cover of tress there it face the problem of losing GPS signal or coverage, at the same time a Wi-Fi network can be found available. This guide to look for a mechanism to solve this problem, This paper present a model to trace and determine locations by making use of Wi-Fi which is provided in Smartphones devices and this is to work out the problem mentioned above.