I use every platform necessary to keep me informed. I have a list of sources that I follow on Twitter to keep me updated.
Between Twitter, YouTube, and certain Facebook groups… I also make sure I attend Facebook’s F8 Developer conference every year, and a number of other events held by social platforms. I have coleagues and connections at Twitter, facebook and Google who keep me up-to-date on new features, different strategies, and whatever so I can pass it along, as I now conduct journalist training. One of my must-follows is Matt Navarra, who actually keeps ME very up-to-date on changes - for example, today Twitter is taking over his account! He’s quite influential in our world, and is based in the UK.
I don't do newsletters or podcasts, but I do follow Kara Swishers' "Recode Decode" podcast. Kara is my former boss from Recode, and she's very influential in the tech world, and does a lot of high-profile interviews.
My inbox is flooded with a lot of crap and spam, so newsletters don't really work for me.
Taylor Lorenz and Kerry Flynn are both also good follows. Between all of them, they keep me informed.