The FOIA email confirms previous reports from Politico that Kelly used a compromised smartphone for months. If it's the same incident (the White House never confirmed the original reports), the attack happened during Trump's transition in late 2016 while Kelly was secretary of homeland security.
As we discussed in NYC about the toxic atmosphere here in the D.C. cesspool, my folks are nervous about e-mails you send and ask that you no longer include them on any postings. FOIA is real and everyday here in the cesspool, and even federal court action on personal accounts is real. Then there is the hacking which one of my own personal accounts has suffered recently. I do almost everything now by phone or face-to-face comms.
https://www.engadget.com/2018/06/11/john-kelly-hacked-foia-request/The president is reportedly refusing to upgrade his iPhones, issued by White House IT agencies to make them more secure, calling the process "too inconvenient." As of last month, he hadn't had them checked by security experts for at least five months. To make matters worse, lawmakers have concerns about fake cell towers around the White House that could eavesdrop on smartphone calls.