can I use a charger for my gps or iphone in the rental cars just like I can here in the States?
Gary, the answer is "Yes". Virtually all cars in Europe are 12VDC, negative ground as they are here. English cars used to be positive ground, but I don't believe that's the case any longer. Happy travels!
Ken, (a) what cars are made in England? The only ones now are Morgans, Nissans, and Minis. Can't speak for Morgans, wierd odd creatures that they are - probably both wrong voltage and polarity just to be difficult - but Minis and Nissans are just bog standard. ^ ^ ^ (b) My guess is the OP is unlikely to drive a Morgan.
Yes, it's exactly the same as here.