New mobile platforms are exploding in popularity and present both opportunities and challenges. So far, however, the software stacks implemented on these new platforms look essentially the same as those on today's desktops and use operating system kernels not substantially different from UNIX of the 1970s. We think this is a squandered opportu- nity; these mobile devices have the potential to slough off thirty years' worth of accumulated software cruft and start clean with an application platform that is both friendly to developers and conducive to achieving maximum perfor- mance. We believe that the abstractions used to build today's web applications will be the ancestors of this new platform, an idea this paper begins to investigate. What low-level ser- vices does this future platform require? We answer this ques- tion by studying current web browsers, and list the required services. What performance limitations imposed by current browser abstractions can be eliminated through novel oper- ating systems? We answer this by quantifying the significant "tax" imposed by these penalties. What are some features such a new operating system might have? We present ten- tative answers to this question as future work, motivated by our profiling results. We also raise the question of whether virtual memory is necessary in such a system.