The Fon WiFi app connects you to millions of hotspots all over the world. Once you've signed into the app and activated a timed access pass, you'll automatically connect to nearby hotspots, even when the app's closed.
You can buy passes whenever you want and save them to use later. Don't worry, your timed pass won't start until you've connected to the first Fon hotspot. And remember, you can use passes to connect to WiFi on multiple devices.