Arpu might sound like a character from an Icelandic animation series, but it was without doubt the star of last week's 3GSM mobile telephony conference in Cannes. Increasing the average revenue per user is what Europe's mobile carriers are relying on to bail them out of the €100bn ($87bn) hole they dug at the height of the telecoms boom.

Mobile operators believe that wireless data services and the mobile internet will dramatically boost the revenues from mobile subscribers. However the price of Europe's third generation mobile licences combined with the infrastructure cost needed to build up the networks has dealt a heavy blow to the entire food chain of the wireless ecosystem.