There are generally two ways to get data from an Arduino to cosm (the online data management tool) - using an Ethernet connection or via a PC that's connected between the Arduino and the Internet. However Arduino forum member "kerimil" demonstrates another version that uses an Android device for the Internet connectivity. In his example, the Arduino captures the data and sends it via a serial Bluetooth link to the Android device running a simple app he has created. Certainly a different approach, which is explained in the following video:
Thankfully the Arduino sketch and Andrdoid app code have been provided, so visit the Arduino forum for more details. for more, we're on twitter and Google+, so follow us for news and product updates as well.
If you're looking for a more direct method of feeding data to cosm, consider one of Ethernet-enabled boards, such as the Freetronics EtherTen - the Arduino Uno-compatible with onboard Ethernet, microSD socket and optional PoE: