With a device cloud, tester or the organization does not need to maintain a physical lab or physical devices. The devices are available on the cloud, and can be accessed from anywhere for testing.
When a device cloud or device farm is used, it can prove economical too because payment is according to usage only, unlike a physical lab where every device has to be bought and maintained.
In addition, on a device cloud, different versions of the same OS can be easily accessed which can be difficult and costly to maintain by a person or organization.