I've been a user since it was a Kickstarter project. It works quite well, actually. The device comes with a globally activated SIM card inside that sends an email/sms to you every time in you in a new location. There's also an Android/iPhone app that has a a bluetooth locator that you can pair with the device so you can track the proximity of your luggage inside the airport. The location is also shown on the app but it's just a webview of the website.