And the president does seem to be aware of the security risks of open phone lines after it was revealed last week that senior aide and Trump's son-in-law Jared Kushner sought to open a secure line to Moscow from within a Russian diplomatic building during the transition.
As unsettling as it would be for USA antagonists (and allies) to tap Trump's personal unsecured cellphone, there's an even bigger worry: the possibility that that same device could be turned into a remote listening device to eavesdrop on even his in-person conversations.
In a scathing article published in the New York Times, sources say that former FBI Director James Comey was forced to repeatedly fend off attempts at friendship from the President.
There's no reason to expect that as soon as Trump scribbled out his phone number on a dirty napkin for a foreign leader, that same napkin wasn't immediately transferred to the country's intelligence agencies.
In Comey's case, to be "friends" with the President meant that he was unfit to investigate the POTUS, an action that Trump was clearly pursuing.
President Donald Trump attends a National Day of Prayer event at the Rose Garden of the White House in Washington on May 4, 2017. The song's refrain says "you used to call me on my cell phone". "It was bad enough there was going to be a handshake". But Trump pulled him into an embrace and Comey didn't reciprocate. If you would like to discuss another topic, look for a relevant article.
We don't know exactly what security precautions might have been taken, but one clue comes from a recent reports that Trump has swapped his ancient Android phone for an iPhone. It is not only tradition for world leaders to speak publicly, but for transcripts of those conversations to be provided to the press and public at-large. He can not simply call him on a mobile phone or send a couple of text messages.
Is it really possible that we're still debating whether high-level government officials should be communicating through personal devices or servers?
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Apple says payouts from App Store total $70 bn
That might be the best news yet for companies that have worked to convince smartphone users to pay for content on their phones. With today's announcement, Apple is keen to show that it's continuing to yield benefits to app makers and publishers.
Nest security camera knows who's home with Google face tech
It can, for example, easily identify people and send you an alert to your device, so you know who's walking around in your home. The camera also comes with a night vision mode thanks to its two infrared LEDs which are nearly invisible to the human eye.