Mobile devices are increasingly becoming the primary device to access the Internet. Despite this thriving popularity, the current mobile ecosystem is largely opaque because of the vested monetary interests of its key players: mobile OS providers, creators of mobile applications, stores for mobile applications and media content, and ISPs. This problem of opaqueness is further aggravated by the limited control end-users have over the information exchanged by their mobile devices. To address this problem of opaqueness and lack of control, we create a user-centric platform, Meddle, that uses traffic indirection to diagnose mobile devices. Compared to an on-device solution, Meddle uses two well-known technologies, VPNs and middleboxes, and combines them to provide an OS, ISP, and access technology agnositic solution. We use Meddle for controlled experiments and an IRB approved study, and ob- served that popular iOS and Android applications leak personally identifiable information in the clear and also over SSL. We then use Meddle to prevent further leaks. We also use our platform to detail the network characteristics of video streaming services, the most popular Web-service in the current Internet. We observe that the network traffic characteristics vary vastly with the device (mobile or desktop), application (native applications and also between individual desktop browsers), and container (HTML5, Flash, and Silverlight). This observation is important because the increased adoption of one application or streaming service could have a significant impact on the network traffic, for example, an increase in the usage of mobile applications.