Microsoft’s efforts in the mobile market have been riddled with failure, but the one shining star has been the company’s Surface line of tablets. Considering the success of the Surface and the Surface Pro, many people are expecting Microsoft to introduce a Surface Phone in the near future, and while we don’t exactly have an official confirmation that such a device is in the works, the company’s CMO has claimed that the company is working on a smartphone that’s the “spiritual equivalent” of the Surface tablet line is being made.