Wireless Key FinderWith GPS remote control with 4.0 wireless system, you can easily search/locate lost items. Item locator with app supports iOS and Android phones. You can download iSearching app from Apple Store or Google Play. (Note: iOS 8.0 or above / Android 4.3 or above) Two-way SearchWhen you want to find the target object, just click the reminder in the app and the tracker will send an alarm for you recall the location of the object. When you are looking for your phone, you just need to press the button on the tracker twice in quick succession and your phone will sound an alarm whether your phone is muted or not. Smart disconnection reminder If the mobile phone and the wireless tracker are not within the effective range, the mobile phone and the finder will remind you. The APP saves the location where the item was last disconnected from the mobile phone to narrow down the search area. It is a great gift for those who forget some things. Effective Coverage The effective distance between mobile phone and GPS button sight is about 15-30 meters indoors and about 25 to 50 meters outdoors. In case of obstacles, the effective distance is the shortest distance Small and portableThe finder is very small and light, you can put it in your wallet, hang it on your backpack back, your suitcase and your keys. Easy to carry. There are 4 trackers in our package which can meet your additional needs.