Seems I am not done with the Android porting just yet after all. One more porting day..
Last night I managed to get all of Yesod to build for Android. I even successfully expanded some Template Haskell used in yesod-form. And am fairly confident I could manually expand all the TH in there, so it's actually useable without TH. Most of the TH is just commented out for now.
However, programs using Yesod didn't link; lots of missing symbols. I have been fighting to fix those all day today.
Finally, I managed to build the yesod-pure demo server,
and I have a working web server on Android! It listens for requests, it logs
them correctly, and it replies to requests. I did cripple yesod's routing
code in my hack-n-slash port of it, so it fails to display any pages,
but never has "Internal Server Error" in a web browser been such a sweet
sight. 
At this point, I estimate about 1 or 2 weeks work to get to an Android webapp. I'd need to:
- More carefully port Yesod, manually expanding all Template Haskell as I went, rather than commenting it all out like I did this time.
- Either develop a tool to automatically expand Hamlet TH splices (preferred; seems doable), or convert all the webapp's templates to not use Hamlet.
I've modified 38 Haskell libraries so far to port them to Android. Mostly small hacks, but eep this is a lot of stuff to keep straight.