O2 (UK) Telefónica O2 had a long-standing relationship with Arsenal F.C., being their shirt sponsor until the end of the 2005/2006 season. In 2005, a three-year deal was signed that saw Telefónica O2 become the team's exclusive mobile communications partner. O2 were the main sponsor of the Channel 4 reality TV show "Big Brother" from its second series (as BT Cellnet) in 2001 until its fourth series in 2003. They also sponsored the spin-off shows "Celebrity Big Brother 2" in 2002 and "" in 2003. In total O2 sponsored five series of the show. O2 sponsored music festivals, the Wireless Festivals, from
O2 (Ireland) Internet offered 1GB of data and 350 any network texts. Same terms applied as per Freedom talk. In December 2013 the data allowance of 1GB was increased to 7.5GB which O2 advertised as Unlimited Internet. Along with the new price plan O2 also launched a vast amount of prepay addons such as Talk, Text, Data, International Talk and International text. In 2010, O2 underwent a restructuring phase, implementing a number of cost-cutting measures which involved outsourcing internal divisions to external companies. O2's IT division was outsourced to IBM Ireland, while the "Network Operations" division was outsourced to BT Ireland ("who