What can I say, BRILLIANT! Warns of all mobile and fixed cameras including average speed cameras, is very accurate and will work in conjunction with an iPhone navigation app. Weekly database updates are prompted as you launch the app on the iPhone and downloading new data is quick and efficient over WiFi or 3G.
I have tried others but this is the best. I had a recent problem when I upgraded to a new iPhone and sent an email to support. Within a very short period of time they responded and solved the problem – superb customer service. Highly recommend this app.