Uber is the most emblematic example of the service platforms that are challenging regulators and antitrust agencies all over the world. Should regulations adapt to the new services of the digital economy? Should competition law change its paradigm in relation to the sharing economy? Despite the growing expansion of these services, in most countries there is still no regulatory framework addressing these problems. This article firstly analyzes the peculiar business model adopted by Uber and the antitrust concerns that it could nourish. And, in so doing, the paper pays heed to the approach that antitrust authorities should have towards the complex rivalry between (regulated) incumbents and (unregulated) new entrants. Then, the paper considers the legal nature of the services provided by Uber, i.e. whether they should be considered as transport services or as services of the information society. Either ways, the chosen characterization will indeed affect the law applied to all digital platforms. The analysis, which adopts a comparative approach, focuses on the European context where national courts are in great turmoil and the CJEU has recently issued a preliminary ruling on the nature of Uber services.