Smartphone data is key for using apps and browsing the internet on the move, but most phone tariffs limit how much you can use.
It wasn't always like that, though - when smartphones first went mainstream several years ago, network operators brought out plans with unlimited data.
But as more applications started hooking up to the web, these plans soon became scarce and expensive, and became subject to fair usage limits.
Skip forward to today and 4G LTE networks are commonplace, but finding an unlimited data package for a reasonable price is a difficult task.
So, can deals still be done without breaking the bank? IT Pro looks at the networks and sees which ones give you the most data for the best price.
Three
About the only mainstream network offering unlimited data, not only does Three have an all-you-can-eat package, it also doesn't charge any extra for its 4G service.
While it says it doesn't have any fair usage policies, on its all-you-can-eat plans only 4GB of data can be used as a personal hotpot.
For one of these plans with a Samsung Galaxy S6 (32GB), you will pay 35 per month with no upfront cost. An iPhone 6 (16GB) is 44 per month with a 99 upfront cost.
O2
O2 stopped giving out unlimited data plans a while back, so customers are limited to packages ranging from 100MB up to 20GB. The bigger the data package, the higher the cost, but the price per GB goes down.
For example, a Samsung Galaxy S6 with 20GB of data will cost 54 per month with no upfront cost not cheap, but a better deal than its 1GB tariff, which costs 37.50 per month with a 29.99 upfront cost.
A 16GB iPhone 6 would cost 49 per month for 5GB of data (no upfront cost). For 20GB of data, the price rises to 59 per month.
EE
EE were the pioneers of 4G in the UK, coming out with its next generation network months before anyone else. There are many tariffs for choose from, ranging from 500MB to 20GB, but no unlimited data packages.
Its 20GB tariff does include unlimited minutes and texts per month for 54.99 per month with a 9.99 upfront cost; this gets you an iPhone 6 1GB handset. There are similar costs for the Samsung Galaxy S6. 20GB of data with unlimited texts and calls costs 54.99 with a 9.99 upfront cost.
For mobile, EE seems to top out at a 20GB limit while mobile broadband dongles, such as the Osprey 2 mini offers 25GB of mobile data (no voice, texts) for 30 (39.99 upfront cost).
Vodafone
Vodafone doesn't do unlimited data packages. But the network provider does throw in some great value add-ons such as Sky Sports for six months, Now TV or Spotify Premium membership for two years.
A 16GB iPhone 6 with 25GB of data (unlimited voice/text) costs 65 per month with no upfront cost. The Samsung Galaxy S6 (32GB) with 25GB of data costs 61 per month with 9 upfront costs. While not the best value, the add-ons could sway some people.
TalkTalk
TalkTalk is one of the companies to offer unlimited data on its mobile packages, but there is a catch; you have to be an existing customer of the firm, and this generally means subscribing to its fixed broadband or TV packages.
This SIM-only deal appears to be the best on offer, if you just happen to be an existing TalkTalk customer. It also offers unlimited calls and texts too. If you leave TalkTalk and keep the mobile tariff, the deal switches to 2,000 minutes, unlimited texts and 2GB of data per month.
BT Mobile
While BT is in the process of buying EE, we don't know for how long the telco will offer something separate from its newly-acquired 4G network. What we do know is that it doesn't offer unlimited data.
Prices vary depending on whether you are a BT customer or not. For non-BT customers a SIM-only deal for 20GB of data costs 25 per month, and that also nets you unlimited calls and texts on a 12-month contract. If you have BT broadband, this gets a 5 per month discount.
Tesco Mobile
Another mobile virtual network operator, Tesco Mobile's data allowances max out at a paltry 8GB per month - hardly unlimited. For this, a 16GB iPhone 6 handset will cost 47.50 per month with no upfront costs. A Samsung Galaxy S6 with 8GB of data, 5,000 minutes and 5,000 texts, costs 49 per month.
