Unlimited, zero-rate and free data – most MNOs don’t currently seem to be able to think more creatively than that in the battle to win consumers. The US market has been shaken up by the return of unlimited plans as Verizon and AT&T respond to T-Mobile’s Uncarrier and Binge On deals (Sprint always had unlimited in some deals), while TMO’s influence is being felt further afield too, with copycat launches in the UK and elsewhere. So marked is the fall in data prices for consumers that one CEO, Andrew Penn of Telstra, is even predicting this will reach zero in the next 5-10 years. He told the recent Mobile World Congress Shanghai conference that operators must diversify away from connectivity…