The T-Mobile Sidekick smartphone is a re-branded version of the Danger Hiptop.

The statement is true. The T-Mobile Sidekick smartphone is indeed a rebranded version of the Danger Hiptop. This can be attributed to the fact that Danger, Inc., a company specializing in mobile communication and data services, originally developed the Hiptop device. However, when it came to marketing the device, T-Mobile acquired the rights to sell it under their brand, thus rebranding it as the T-Mobile Sidekick. Despite the rebranding, the underlying technology, design, and features of the device remained similar to the original Danger Hiptop.