Barack Obama kept his beloved BlackBerry when he became president despite objections from the secret service. Photograph: Charles Ommanney/Getty Images

For years, the well-connected world leader would use nothing but a BlackBerry to get their email on the move – and it is still Barack Obama's phone of choice. He uses a model specially enhanced by the US National Security Agency. But the news earlier this month that the White House Communications Agency is testing other phones, including models by Samsung and LG, sent shivers through fans of the struggling Canadian smartphone company, which has just announced an annual loss of .8bn.

For a world leader, security is much more than just having a passcode on your phone; it also means protecting it against attempted incursions from all the amateur and professional hackers, and more importantly spy agencies, who want to know to whom, when, what and where you have been speaking and reading. For a country's leader to have their phone eavesdropped is the ultimate failure of their national spy agency, and a huge loss of face. With enhancements, BlackBerry has been the spy agencies' phone of choice to guard against that so far. Now, though, Apple and Samsung – the two largest makers of smartphones – are starting to knock on the security services' doors.

And what if BlackBerry goes away? Though it may have pulled out of a death spiral, BlackBerry's position as the phone of choice for top executives is less clear – and Apple has been touting (pdf) ever-improving security on its iPhone, which has been edging out BlackBerrys even in financial institutions such as Goldman Sachs, once a redoubt for the keyboard-reliant phones. Yahoo, Pfizer and Halliburton have all said sayonara too.

As rival devices improve their security, it could only be a matter of time before Apple or Samsung becomes the US leader's phone – perhaps not during Obama's presidency, but in his successor's. Though the White House press secretary has insisted that "the executive office of the president is not participating in a pilot programme" to replace Obama's BlackBerry, it might only be a matter of time – though if Hillary Clinton succeeds him, her well-known affinity for it could extend its survival just a little longer.

Germany

Angela Merkel uses a Nokia Slide. Photograph: Fabrizio Bensch/Reuters

Angela Merkel's mobile became the most famous phone in world politics when it emerged in October last year that the NSA had been monitoring the chancellor's calls. But she has at least two phones she uses on a regular basis: the one that was allegedly monitored by US intelligence services, a Nokia 6260 Slide, was reportedly used for party matters only. For state affairs, Merkel uses a BlackBerry Z10, fitted with an encryption chip by Secusmart. The Düsseldorf company insists its software remains hack-proof and continues to market its device as the "Kanzler-Handy", the chancellor mobile. Philip Oltermann in Berlin

US

One of Barack Obama's first battles when he arrived in the White House in 2009 was to keep his beloved BlackBerry, despite objections from administration lawyers and the secret service. "I'm still clinging to my BlackBerry, " he said at the time. "They're going to pry it out of my hands." Ever since, the US president has been permitted a modified BlackBerry handset, with enhanced encryption. Only a handful of senior White House officials and family have his personal email address. Three months ago he told a group of young people: "I am not allowed, for security reasons, to have an iPhone." Paul Lewis in Washington

Source: www.theguardian.com