does not logging out of wiki use up my data while I am not actually on line ? I have 2gb allowance on my phone, lately it has been running out very quickly. I have just checked my account on EE and I says I have used 75% of my allowance after just over a week. Cheers

Do you have GPS on, apparently that eats data as does Bluetooth.

Thanks Salmon but yes both are off.

Interesting: I have both GPS and Bluetooth enabled on my phone but I've only used 52Gb of data out of my 500 Gb allowance in 24 days.

Chris, are you sure that is GB not MB. 500GB would seem to be way too much.
Actually I just realised what I wrote was incorrect. GPS uses lots of data but Bluetooth uses lots of battery power.Both will check locations "regularly" however so will use data.

Download the app Advanced Task Killer:

https://play.google.com/store/apps/details?id=com.rechild.advancedtaskkiller&hl=en_GB

You'll see which apps open themselves up and transfer data without your knowledge. For example, I rebooted my phone this morning, killed some apps, yet an hour later the following have started without my say so:

Google+
Messenger
Yahoo Mail
WhatsApp

All of which use 3G if allowed.

Personally I keep 3G off unless I need to search for something. It saves power and data.

GPS only uses data if you allow Google to track your location via 3G to aid accuracy.

Its not your gps as thats a different technology. Gps typically flattens your battery on older devices, but on new once it pretty good as it turns its self off when not required.

I suspected its background services.
These are background send and receive with emails, push notifications via Facebook book.

If you let us know the make and model we can advise better and how to make the correct settings.

Whoops ive repeated Gibbo, but as he says too.

Thanks all, it is a samsung S5 sm-g900f. Cheers

Weather - Travel etc those apps put a right hole in my allowance, constantly updating.

Yes, you're right, of course: MB. I still use virtually none, even though I have GPS turned on, but I don't think anything's using it.

Samsung has a screen that shows which apps are eating your data.

It also depends which version of Android your using. Lollypop or other.

Im on lollypop so if i go into settings then Data usage i get a full breakdown.

Thanks Mark, just been through them and it looked like gmail was using a lot of data as I get email notification when I get a PM, I've now switched it off. Also disabled some others. Cheers again.