With incentive announcements from EE and O2 rattling around, Vodafone has pitched in with its own ideas to entice new customers. It has increased the data allowances on its Red Value bundles and is now offering 4G by default for all monthly handset agreements.

The carrier's Red Value bundles are 24 month price plans that include bonuses, such as a Now TV Entertainment Pass, Spotify Premium or Sky Sports mobile subscriptions. And because they each impact a customer's data allowance, it makes sense for Vodafone to increase the monthly data caps.

Customers now also get inclusive calls to the UK from within set European countries.

Red Value bundles that include video or music streaming now start at 4GB of data a month, going up to 25GB of data depending on the price plan.

Vodafone has also announced a "Fixed Price Promise" that ensures there will be no rise in monthly costs for its customers for the duration of a contract.

From January 2014, UK independent communications regulator Ofcom enforced the ruling that a customer could cancel his or her contract without penalty if prices were raised during the contact's term. Vodafone's new measure ensures that its customers won't have to.

"With our... Fixed Price Promise, Vodafone customers have the flexibility and security to enjoy more of what they love safe in the knowledge their line rental cost will remain the same for the contract term, making Vodafone the network they can depend on," said Cindy Rose, consumer director at Vodafone UK.