I found this post late but I know why there are no apps showing F1 live or with proper Live timing.
The Formula 1 and its associate organisations are becoming a sort of monopoly for live timings, basically de-activating the services which rely on their servers for live timing. I think there are very few libraries still able to provide live timing but will be stopped soon IMO.
The formula 1 tv coverage rights are also too restrictive, so app found doing so will get a cease and desist. I have been trying all the formula 1 apps on windows phone but I was not satisfied with the granularity of data provided by them. So, I developed my own which I kind of use myself.
I hope windows phone devs can really tap into Ergast's F1 Api and produce stunning apps. This API does not provide live timing, but has race data since 1950 and every detail you might need in the past 10 years.
I wish F1 could release something officially soon, I mean Windows 8 outsold Macs in 10 odd days. Either they are friggin' lazy or are developing something albeit at a snail's pace.