Pool, Getty Images 
 
 Who's got two thumbs and a Secret Service-approved phone to tweet from? 
 
 On arriving in Washington on Thursday ahead of his inauguration, Donald Trump handed in his Android device in exchange for an unidentified locked-down phone, according to the Associated Press. 
 
 The phone comes with a new number that is known only to a limited number of people. This marks a big change for Trump, who's frequently on the line with friends, business contacts, reporters, foreign leaders and politicians. 
 
 Larry Johnson, who worked at the Secret Service from 1982 to 2006, said a smartphone given to a president would have extremely limited uses. "It's not really good for much," he said. 
 
 It's possible Trump's Twitter account would be operated from another phone, said Johnson, who now works as an executive at cybersecurity company CyberSponse. 
 
 But that's not where the phone's limitations would end. "You can't make a phone call, because it's too easy to be intercepted," Johnson said. "I can scare you with how easy it is." 
 
 The Secret Service declined to comment for this story. 
 
 Now playing: Watch this: Trump trades in Android for a mystery phone 
 
 Barack Obama was the first president to use a mobile device approved by security agencies because of hacking concerns. Initially he had a heavily modified BlackBerry and later switched to another phone that had most features disabled. He was not known to use it for making or receiving calls, but it was one of few devices that had access to the @POTUS Twitter account. 
 
 Trump said earlier this week that he will keep using his existing Twitter account to communicate on social media, in addition the the @POTUS account. 
 
 Originally published Jan. 20, 2017 3:24 a.m. PT 
 
 Update, 10:50 a.m. PT: Added comment from retired Secret Service agent Larry Johnson. 
 
 What does a Trump presidency mean for tech? Some say it might not be as bad you think. Others say his potential influence on the industry is "alarming." 
 
 Life, disrupted: In Europe, millions of refugees are still searching for a safe place to settle. Tech should be part of the solution. But is it? CNET investigates. ||||| WASHINGTON (AP) — A few hours after President-elect Donald Trump was briefed by intelligence officials about Russian meddling in the election, an Associated Press reporter called his cellphone seeking an interview. 
 
 The call went to voicemail and the reporter did not leave a message. About an hour later, Trump called back. 
 
 It's hard to imagine many politicians — particularly one about to become president of the United States — calling back an unknown number on their cellphone. 
 
 With Trump, it's simply how business gets done, whether he's fielding calls from real estate partners and longtime friends or foreign leaders and congressional lawmakers in the weeks after the election. 
 
 But as Trump prepares to take the oath of office Friday, the future of his ever-present Android smartphone is now a matter of national security. On Thursday, he told a friend that he had given up his phone, as security agencies had urged him to do. It was unclear whether he was following the lead of President Barack Obama, the nation's first cellphone-toting president, who exchanged his personal device for a Blackberry heavily modified for security purposes. 
 
 The friend who spoke with Trump spoke to The Associated Press on the condition of anonymity in order to disclose the private conversation. 
 
 The presidency has long been a lonely, isolating office, with security concerns keeping the commander in chief at a distance from the public. Under Obama, worries about cyber intrusions — particularly by foreign governments — pulled the president's technology deeper into the security bubble as well. Many of the functions on Obama's Blackberry were blocked and only a handful of people had his phone number or email address. 
 
 Trump doesn't email, but he uses his phone to tweet — something he's made clear he plans to continue in office. He's known to make calls early in the morning and late at night, often seeking input from multiple sources when making a decision. Sometimes he leaves a voicemail. 
 
 Christopher Ruddy, the CEO of Newsmax and a friend of the president-elect, described Trump's phone etiquette, as "just like one of his speeches, it's very stream of consciousness." 
 
 Sen. Bob Corker, R-Tenn., called Trump "amazingly accessible," saying the president-elect picks up his phone even when he doesn't know who is calling. 
 
 "My phone says, No Caller ID, so I'm not saying that it has anything to do with me," Corker said. "Nobody knows who it is that's calling when I'm calling." 
 
 Foreign leaders and diplomats took advantage of Trump's accessibility in the days after his election as they scrambled to find ways to reach him. Some called into Trump Tower hoping to be transferred to the president-elect's office. Australian Prime Minister Malcolm Turnbull got Trump's cellphone number from the golfer Greg Norman. 
 
 Trump's accessibility can create headaches for his aides, who can't always control who he's speaking to or what he's saying. After actress Meryl Streep blasted Trump during a Golden Globes speech earlier this month, a New York Times reporter called the president-elect at midnight to get a response. Trump's criticism of Streep dominated the news the following day, overshadowing his team's planned agenda. 
 
 For Obama, getting to use a Blackberry in office was considered a victory. He later switched to an iPhone that allowed him to send and receive email from a limited group of people, surf websites and read the news. 
 
 But Obama wasn't known to use his cellphone to make or receive telephone calls, according to individuals familiar with his technology use. Even senior government officials didn't have the number and instead reached the president through the White House switchboard. 
 
 The president also used the switchboard to place his calls, said the individuals, who weren't authorized to speak publicly and requested anonymity. 
 
 Obama had a phone in his control that he used to tweet, one of the only devices with access to the official presidential Twitter feed due to hacking concerns. But Obama rarely hit "send" on a tweet himself, and never without coordinating it with his staff, the individuals said. 
 
 If Trump does get rid of his cellphone, it could end up with a home not far from the White House. 
 
 Curators at the Newseum, which chronicles the First Amendment and the evolution of electronic communication, reached out to Trump's campaign in November about the prospect of acquiring his Android phone. They haven't heard back, said Carrie Christoffersen, the museum's curator of collections. 
 
 ___ 
 
 AP writers Julie Bykowicz, Josh Lederman and Ben Nuckols contributed to this report. 
 
 ___ 
 
 Follow Julie Pace at http://twitter.com/jpaceDC ||||| poster="http://v.politico.com/images/1155968404/201702/631/1155968404_5336286849001_5336238322001-vs.jpg?pubId=1155968404" true Sean Spicer targets own staff in leak crackdown The push includes random phone checks overseen by White House lawyers. 
 
 Press secretary Sean Spicer is cracking down on leaks coming out of the West Wing, with increased security measures that include random phone checks of White House staffers, overseen by White House attorneys. 
 
 The push to snuff out leaks to the press comes after a week in which President Donald Trump strongly criticized the media for using unnamed sources in stories and expressed growing frustration with the unauthorized sharing of information by individuals in his administration. 
 
 Story Continued Below 
 
 Last week, after Spicer became aware that information had leaked out of a planning meeting with about a dozen of his communications staffers, he reconvened the group in his office to express his frustration over the number of private conversations and meetings that were showing up in unflattering news stories, according to sources in the room. 
 
 Upon entering Spicer’s office for what one person briefed on the gathering described as “an emergency meeting,” staffers were told to dump their phones on a table for a “phone check," to prove they had nothing to hide. 
 
 Spicer, who consulted with White House counsel Don McGahn before calling the meeting, was accompanied by White House lawyers in the room, according to multiple sources. 
 
 There, he explicitly warned staffers that using texting apps like Confide — an encrypted and screenshot-protected messaging app that automatically deletes texts after they are sent — and Signal, another encrypted messaging system, was a violation of the Presidential Records Act, according to multiple sources in the room. 
 
 The phone checks included whatever electronics staffers were carrying when they were summoned to the unexpected follow-up meeting, including government-issued and personal cellphones. 
 
 Spicer also warned the group of more problems if news of the phone checks and the meeting about leaks was leaked to the media. It's not the first time that warnings about leaks have promptly leaked. The State Department's legal office issued a four-page memo warning of the dangers of leaks, and that memo was immediately posted by The Washington Post. 
 
 But with mounting tension inside the West Wing over stories portraying an administration lurching between crises and simmering in dysfunction, aides are increasingly frustrated by the pressure-cooker environment and worried about their futures there. 
 
 Within the communications office, the mood has grown tense. During a recent staff meeting, Spicer harshly criticized some of the work deputy communications director Jessica Ditto had done, causing her to cry, according to two people familiar with the incident. "The only time Jessica recalls almost getting emotional is when we had to relay the information on the death of Chief Ryan Owens," Spicer said, referring to the Navy SEAL killed recently in action in Yemen. 
 
 Ditto also denied the accounts. "This is 100 percent not true," she said Sunday after the incident was reported. "Sean and I have a great working relationship." 
 
 Spicer declined to comment about the leak crackdown. 
 
 The campaign to sniff out a series of damaging leaks, which Spicer is convinced originated from his communications department, has led to a tense environment in the West Wing. During meetings, the press secretary has repeatedly berated his aides, launching expletive-filled tirades in which he’s accused them of disclosing sensitive information to reporters and saying that they’ve disappointed him. 
 
 As word of the hunt has ripped through the office, talk has turned to the question of whether firings are to come. 
 
 Spicer was particularly incensed by the leaks last week that Michael Dubke had been tapped as the new White House communications director — a hire that became public before it was officially announced. 
 
 “In general,” said one senior administration official, “there is a lot of insecurity.” 
 
 While other parts of the White House appear to be stabilizing, the press shop is often a center of frustration about how things are going — and not just from Spicer, who fumes to aides about stories he doesn’t like. 
 
 For Trump, a cable TV addict who has long obsessively tracked news coverage about himself, the ongoing turmoil in the White House communications wing threatens to derail the media narrative that will help to define the opening days of his presidency. His decision to hold a free-flowing news conference last week, two senior officials said, stemmed from a recognition that he was no longer breaking through in a news cycle that had turned against him. 
 
 “He reached a breaking point where he wanted to do it himself,” said one senior White House aide. 
 
 It has not been lost on senior White House officials that Spicer is overseeing an overwhelmed press office, where work often begins just after 6 a.m. and ends close to midnight. 
 
 To help streamline the office, the administration has tapped Dubke, a veteran under-the-radar Republican operative known for his organizational skills. Yet the move has infuriated Trump campaign aides, who argue that someone who’d been a vocal Trump supporter — which the establishment-minded Dubke hadn’t been — should have gotten the job. 
 
 “People are on fire about it,” one campaign veteran said of the Dubke hire. 
 
 Multiple former campaign aides said they were under the impression that RNC veterans pushed through Dubke, who is close with Republican strategist Karl Rove, with relatively little consultation with others in Trump world. (Several other people interviewed for the post, including Jarrod Agen, a spokesman for Vice President Mike Pence, and Scott Jennings, a former political aide in the George W. Bush White House.) 
 
 To some degree, the challenge Spicer and other press aides face is unique — they are working for a president who takes an unusually intense interest in the work his communications office does. Trump is known to watch Spicer’s daily press briefings while eating lunch in the White House dining room. While the president was critical of his press secretary in the administration’s first month — especially after he was parodied on “Saturday Night Live” — he more recently has offered the press secretary his private assurances that his job is safe. 
 
 The push to crack down on leaks follows a week in which the president ratcheted up his criticism of the press and condemned the free flow of information from parts of his administration. On Friday, Trump called the media the “enemy of the American people” during a speech at the Conservative Political Action Conference in which he railed against journalists for using anonymous sources. 
 
 “I want you all to know that we are fighting the fake news. It’s fake, phony, fake,” Trump said. “A few days ago, I called the fake news ‘the enemy of the people,’ and they are. They are the enemy of the people. Because they have no sources. They just make them up when there are none.” 
 
 Later on Friday, Spicer blocked certain media, including CNN, The New York Times, BuzzFeed and POLITICO, from attending an off-camera press briefing in his office. Time and The Associated Press boycotted the briefing out of solidarity. 
 
 On Saturday, Trump said he would not attend the annual White House Correspondents' Association dinner in Washington.
– Well, it appears the Secret Service has pried Donald Trump's beloved Android phone from his tweeting fingers. An unidentified friend of Trump's tells the AP the new president handed over his phone Thursday on the advice of security advisers. The New York Times reports Trump's Android was replaced by an encrypted device that received Secret Service approval. Barack Obama, the first president to use a mobile device in office, started with a "heavily modified" Blackberry before moving to a mostly disabled iPhone. The devices were used to check email and news sites but rarely—if ever—for phone calls. This is all likely to cramp Trump's style. A Republican senator says the president was known for answering his phone even if he didn't recognize the number. He would even call back strange numbers that didn't leave a message. A former Secret Service agent tells Cnet Trump is unlikely to be able to use his new device for phone calls because they are way too easy to intercept. Trump's aides—some of whom are excited journalists and others won't have direct access to him—say he's likely to instead go office to office in person to get his "gossip" fix. It's possible he'll still be able to tweet. The Newseum in Washington DC has asked Trump about getting his Android to put on display.