1980s Analogue phones, mostly in-car phones, typically cost £2,000 per unit to buy.
1980s Margaret Thatcher makes first UK mobile phone call on a private-use dedicated mobile network.
1980s First UK mobile licences granted to Telecom Securicor Cellular Radio (TSCR) and Racal Vodafone.
Early 1990s Mobile etiquette standards published by Cellnet in the UK.
1992 First text messages sent.
1993 International roaming begins to take off.
First truly portable GSM (Global System for Mobile Communications) handsets are launched.
1994 Launch of digital GSM.
1997 ESAT Digifone launches GSM network in Ireland, later part of O2.
1998 Viag Interkom launches business in Germany, later part of O2.
1999 Text-messaging volumes grow with launch of InterConnect. UK text volumes reach 1.0 billion.
2000 The UK Independent Expert Group on Mobile Phones (IEGMP) publishes precautionary approach to health and mobile phones – the Stewart Report.
Mobile industry sets strict standards of best practice in building networks and siting masts.
2000–2004 Number of minutes spent making mobile calls in the UK almost doubles to 62.0 billion.
2000 ESAT Digifone bought by BT.
2001 BT’s mobile businesses are de-merged and begin trading under the corporate umbrella of mmO2.
Europe’s first 3G network goes live on the Isle of Man, operated by Manx Telecom.
2002 Launch of the O2 consumer brand in the UK, Germany and Ireland.
2003 O2 UK and Tesco create Tesco Mobile.
Guidance published by O2 on emerging issues, including child safety, sensible use of cameras, health and safe driving.
2004 O2 signs long-term agreement with NTT DoCoMo for i-mode® mobile internet services.
Launch of third generation - 3G - mobile network in the UK, Germany and Ireland.
O2 Germany sets up a joint venture with Tchibo
O2 Ireland sponsors first O2 Ability Awards.
2005 O2 Airwave delivers UK national police communications service and wins Ambulance contract.
Europe's first super-speed 3.5G mobile network launched on the Isle of Man.
New industry content standards, mainly to protect children, signed or implemented in the UK, Ireland and Germany.
Fourth O2 customer service centre opens in Glasgow creating 1,500 new jobs.
O2 mobile TV trials go live in Oxford, UK.
The annual mobile content market in the UK is expected to grow from £868 million in 2005 to £2.5 billion in 2010.
2006 Ring tones are now worth more than the UK market for CD singles.
O2 is acquired by Telefónica, S.A.
O2 announces highest-ever quarter customer growth in the UK and Germany.