There should be a better way to work. Maybe I should setup my cloud server to provide one time stopId and Line info.
It may easily over quota for app engine with iPhone.
Or a way to update the tfl site link and save it on preference. The cost is high when tfl changes. 2 changes on bus and tube on android. And 2 changes on iPhone with a 7 days waiting time. And it happens before once.
It seems that London bus will be better with osm. It has the stopId. There is no need for tfl site. Hopefully.
For London tube, it needs the tfl site to get the stopId. If it fails, it goes to app engine to get stopid. I will have time to release an updated version. Or if it fails, it will download the right tfl URL. I only need to update the tfl new URL. No need to release new version.
A simple tflurl.txt file on app engine.
Edit on 030213. It turns out that it is better than I thought. For london bus, i do not use tfl nearby site at all. I am using its api for nearby. So the tfl site changes does not affect my london bus. I would only need to update my ios london tube!