The mobile phone watchdog has given phone networks a slap on the wrist for not telling us enough about data on our mobile phones -- which all too often leads to a nasty shock when the bill comes in.
The communications ombudsman said networks needed to be clearer about data limits, especially hidden limits.
Chief ombudsman Lewis Shand Smith told the BBC that networks should, "First of all, be very clear about what they mean by unlimited in the advertisements. Secondly, give advice to consumers so they know when they're reaching their limit, and thirdly, give advice on the amount of data that's being downloaded."
The complaints watchdog has received an increasing number of complaints, and believes networks could do more to head off the growing problem of data-related bill shock. Today's smart phones can eat up data at a voracious rate with features such as streaming music and video -- and even when the phone is in your pocket it's likely to be sneakily snaffling more data as apps update themselves.
We've long bemoaned the fact that data tariffs advertised as unlimited are in reality anything but: Internet use on your phone or tablet is subject to a limit on the amount of data downloaded and uploaded. This 'fair use policy' is almost always hidden in the small print. For many customers, the first time they hear about their fair use policy is when their bill arrives -- and the bottom line is somewhat more than expected.
3 and GiffGaff are the only networks to offer truly unlimited data.
The ombudsman also pointed out that when we're using data overseas, European law requires networks to tell us when we're approaching a limit of €50, and must cut us off when that limit is reached. That means no inadvertently running up a bill any higher than about £43 -- a safeguard that would be useful at home too.
If you want to complain about your phone network, the best place to go is Ofcom, the telecoms regulator. You'll find its complaints page here.