The iPhone 6S is on sale today. Offering an improved camera, better build quality and unique new features like Live Photos and 3D Touch, it's one of the best handsets you'll see this year.
But as important as the phone you choose is which contract you go for. Do you want unlimited data? Or would you rather pay less for more limited browsing?
Here's our pick of the best around.
Best iPhone deals for heavy users
If you use your phone a lot for web browsing, emailing, phone calls and text messages, there are plenty of options.
Vodafone offers the 16GB iPhone 6S with no upfront cost and for £44 a month. That gets you unlimited phone calls, unlimited texts and 10GB of data.
Three will give you a little more data for a bit more money. The 16GB iPhone 6S can be yours for £99 upfront and then £48 a month. That gets you unlimited calls and texts and 12GB of data. You can also snaffle unlimited data for £51 a month, plus £99 upfront for the 16GB 6S.
If you want more storage, O2 offers the 128GB iPhone 6S for £9.99 upfront and then £64 a month. That gives you unlimited calls and texts and a whopping 20GB of data.
Vodafone will give you 20GB of data for £50 a month with no upfront cost. That's for the 16GB 6S, with unlimited calls and texts.
Finally, EE matches the 20GB of data and charges £49.99 a month plus an upfront fee of £19.99. That gets you the 64GB 6S with unlimited calls and texts.
Best iPhone 6S deals for lighter users
If you browse, stream and email a lot less, you could pay far less per month.
O2 offers the 16GB 6S for £27.50 a month, which gives you 1GB of data, plus unlimited calls and texts. However, you will have to pay £150 for the phone upfront.
Vodafone offers the 16GB 6S for £44 a month with 2GB of data, unlimited calls and texts, and with no upfront fee. Or with 1GB of data for £39 a month and a £9.99 upfront fee.
EE offers the 16GB 6S with 2GB of data for £34.99 a month, plus an upfront fee of £74.99. That comes with unlimited texts and 1,000 minutes. Or with 1GB of data, the same texts and minutes for £21.99 a month, but a hefty upfront fee of £379.99.
Best iPhone 6S deals for extras and freebies
Don't forget networks offer extra incentives to get you to sign up. Three doesn't charge extra for 4G, for example, and, from certain countries, offers calls and texts to UK numbers for the same price as at home.
O2 offers money-off promotions for high-street shops and restaurants like Boots and Zizzi, plus priority booking at O2 venues.
Vodafone gives certain contracts a choice of free Now TV, Spotify Premium or Sky Sports Mobile TV.
EE, meanwhile, has the fastest and most widespread 4G network in the UK and offers the free Refresh battery recharging scheme. Where coverage is patchy, you can also make and receive calls and send texts over Wi-Fi.