Which uses more data, iPhone 5 or blackberry z10?

I use over 2.5gb a month on my iPhone 5, on vodafone. If I was to get the z10, would this help me. I previously had a blackberry 9300 and that barely used any data although I was on it for the same amount of time. I can't afford to keep going over my contract, also if anyone an recommend a good phone, like a high end smartphone that compresses data usage better?

Added (1). What's a track phone?

Added (2). I can't cancel my contract I would have to pay the rest of my contract price:/ and I don't know whether to get a new phone. I wish I'd of just gone with giff gaff in the first place! Also do you know how I reply on here instead of just adding details?

Added (3). I've done more research and got my answer, they're the same as BBz10 don't have the data compression like the older BB models used to have. Problem solved, I will just have to live with it or wait until a new phone comes out with a good data compression! :/ thanks guys

Which uses more data? A Track-phone, any phone answer. The answer is: Track-phone…

Iphone. If I was you I would get unlimited data from giffgaff for £13 with free calls plus messages!

Data use probably is the same but people tend to use iphones alot more.