Currently have a cheap eBay cigar lighter to USB adaptor with a cheap iPhone data cable but it’s really slow to charge and can barely keep up with the drain when using TomTom.
The expensive options on the apple store get pretty poor reviews so I’d really like a personal recommendation.

I’ve just used the £3.00 ones off ebay… not had a issue. 😕

I tried a kingston one. It didn’t sit properly in the socket and had to be returned.

[edit] Car was a Honda Civic. Not sure if there is anything non standard about Honda cigarette lighter sockets.

I’ve got a belkin one that seems to work just fine.

I have a tiny Belkin one, which is identical in appearance and spec to this one from 7dayshop:-

They knock out 1 amp, which is a fair bit of juice!

No quite identical, the LED’s are different colours. I have the Belkin one. Its really good. I also just bought a couple of the 7day ones, but havn’t tested them yet. Other than LED colour they look the same.

The LED on my Belkin one is blue – exactly like these.

Funny, just checked. My belkin has a green light. The 7day one has a blue. Also noticed that the printing on them is identical, though there are some subtle differences in length of centre pin.