How is Cloud computing different from computing for mobile devices?

Since Mobile devices are getting connected to the Internet in large numbers, we often use Cloud computing for Mobile devices.

In mobile applications, there can be sudden increase in traffic as well as usage. Even some applications become viral very soon. This leads to very high load on application.

In such a scenario, it makes sense to use Cloud Computing for mobile devices.

Also mobile devices keep changing over time, it requires standard interfaces of cloud computing for handling multiple mobile devices.