Sony Mobile had research and development facilities in Lund, Sweden; Beijing, China; Tokyo, Japan; and San Francisco, United States.

[11][12] Swedish company Ericsson had been making mobile cell phones since the 1980s, their first very handheld device being the Hotline Pocket introduced in 1987.

[15] Nokia had already begun to obtain parts from alternative sources, but Ericsson's position was much worse as production of current models and the launch of new ones was held up.

[19] Speculation began about a possible sale by Ericsson of its mobile phone division, but the company's president, Kurt Hellström, said it had no plans to do so.

To this end, it released several new models which had built-in digital camera and colour screen which were novelties at that time - examples include the Sony Ericsson T610, the P800 UIQ smartphone, and later the K700 handset.

[22] In 2005, Sony Ericsson introduced the K750i with a 2 megapixel camera, as well as its platform mate, the W800i, the first of the Walkman phones capable of 30 hours of music playback.

Also in 2005, Sony Ericsson agreed to become the global title sponsor for the WTA Tour in a deal worth $88 million US dollars over 6 years.

The eclipse of the Symbian operating system, initially by Apple's iPhone, and then by Google's Android, has affected Sony Ericsson's position in the market.

In June 2008, Sony Ericsson had about 8,200 employees, it then launched a cost-cutting program and by the end of 2009 it had slashed its global workforce by around 5,000 people.

It has also closed R&D centres in Chadwick House, Birchwood (Warrington) in the UK; Miami, Seattle, San Diego and RTP (Raleigh, NC) in the USA;[29] The Chennai Unit (Tamil Nadu) in India; Hässleholm and Kista in Sweden and operations in the Netherlands.

[4] On January 7, 2013, Sony Mobile completed moving its headquarters from Lund, Sweden to Tokyo, Japan in order to fully integrate with its parent company.

[45] Sony Mobile was the fourth-largest smartphone manufacturer by market share in the fourth quarter of 2012 with 9.8 million units shipped.

[52] In the last quarter of 2015, Sony Mobile had the highest per-handset-profit and average selling price of all major Android handset manufacturers.

[53] However, in terms of market share, Sony Mobile dropped out of the top 10 smartphone vendors globally for the first time in the first quarter of the year.

Sony Electronics Corporation will incorporate the three businesses that comprise its Electronics Products & Solutions ("EP&S") segment (Imaging Products & Solutions, Home Entertainment & Sound, and Mobile Communications) and related global sales and marketing, manufacturing, logistics, procurement and engineering platforms.

As of that year, Sony Ericsson had 425 employees in Research Triangle Park; the staff had been reduced by hundreds due to layoffs.

[61] Stacy Doster, a spokesperson of Sony Ericsson, said that the proximity to Hartsfield-Jackson Atlanta International Airport's flights to Latin America and the operations of AT&T Mobility influenced the decision to move the USA headquarters.

[66] For the Japanese market, Sony Ericsson also produced Linux and Symbian-based MOAP handsets for NTT DoCoMo, as well as REX OS for au/KDDI.

In 2011 Sony Ericsson carried a range of mid and high-end Android smartphones all using the same SoC, only differentiating in form factor, screen size and multimedia capabilities.

[77] In 2010 the LiveView smartwatch was launched,[78] featuring a colour OLED display that let the user view notifications and control the music player.

[86] During 2010, in 11 months, Sony Ericsson's Facebook fan count rose from 300,000 to 4 million to become the 40th-largest brand on the social networking site.

It will also analyse the top commenters on the Facebook page and ensure engagement through special content and offering these fans the chance to visit Sony Ericsson offices.

According to the head of global marketing partnerships,[88] Stephan Croix, “our sport sponsorships allow us to promote our phones in a subtle and authentic way to our fanbase.