Help please. I have my first smartphone (Samsung Galaxy W on T-Mobile), which I am very happy with. However, I need some advice:

1. If I load up music onto the phone, and play it through my car radio (A Golf, with a cable fixed into the radio ready to plug the phone into) - will playing music for several hours drain the phone battery. What battery useage can I expect playing music like this?

2. I am soon to go on holiday in France driving around. If I use the Navigation app which came with the phone, and switch the GPS on for several hours, will it drain the battery quickly?

3. If I use the GPS function (I will switch the packet data off when I leave these shores to avoid a huge bill) for navigation in the car, do I avoid any additional costs?

Thanks in advance for any answers. I am in new territory here!

1. With the screen off, you'd get a healthy number of hours out of the battery. Volume etc. affects performance but playing music isn't a massive drain.

2. GPS and screen on are both battery killers. GPS only drains battery when it's in use (ie. you don't need to turn it off all the time), but when using satnav it is VERY much in use!

3. Google Navigation needs a data connection or it won't function. You can buy offline navigation apps (eg. Route 66 maps, CoPilot, etc.) which will then work without the packet data, but the stock navigation system will not work without data.

As said, google maps needs a data connection whilst planning routes. It will cache the route once planned so you won't need more data once on the move (unless you go off route). You could always use Wi-Fi to plan the route if you have it where you're visiting.

As for using the phone in the car, buy a cigar to USB adapter or a universal car charger


Rik.

GPS is a huge battery killer - I forgot to plug the car charger into the car one time (plugged it into the phone though!) and the battery had drained from about 80% to dead in the time it took to drive from Nottingham city centre to Uttoxeter.

Get a car charger! However some of them are a bit underpowered and can't charge a modern phone under heavy load (which GPS is) - http://james.cridland.net/blog/four-...gle-nexus-one/ - A Sony Ericsson or HTC one will be fine (and I'm sure a genuine Samsung one would be too).

Not too sure how well they will play the audio together - on my satnav app the music dips in volume, but is noticeably louder than music and you can't adjust them separately.

The cost of any data used away from your home country is far more important than how much battery power is used !

Use a satnav better all round !

Thanks for all your valuable advice!

Do not bother with a a car phone adapter, a dual USB car adapter is more useful.

About £2 at most via ebay.