19 per cent of mobile users dont know what network operator theyll be on once their current contract expires, according to ICM Research.

Almost all operators are vulnerable to losing market share, according to the study. The three biggest networks – O2 (21 per cent of mobile users), Orange (22 per cent) and Vodafone (19 per cent) – each potentially stand to lose between three and six per cent of their customer base. Two per cent of mobile users, meanwhile, are intent on jumping over to EE when it launches in the coming weeks.

Samsung seems to be the manufacturer benefiting the most from rising smartphone penetration. Samsung Android devices from nine per cent up to 14 per cent between June and September. Thats driven primarily by customers on pay-monthly contracts, where Samsung Android devices has increased to a total 20 per cent, up from 13 per cent in June.

“As we’ve seen before, both mobile operators and handset manufacturers are vulnerable to losing market share,” said ICM associate director Jamie Belnikoff. “However, with both the arrival of EE, offering 4G services, and the iPhone 5, customer retention efforts really do need to be sharpened. It will be interesting to see how the market develops over the next few months once both EE and the iPhone 5 have had time to bed in.”