"...as carriers prepare to shut down their 2G and 3G towers, Amazon is warning longtime customers that their old Kindles will lose their wireless capabilities–a big bummer if you own a Kindle that lacks Wi-Fi support." To read the rest of the article: https://www.reviewgeek.com/93544/some-amazon-kindles-lose-internet-access-soon/. So the affected Kindles (of which my old Paperwhite is one because of course it is, sigh) will still be able to download ebooks only by plugging directly into a PC, no longer just using a cord and a wireless router. The article gives a link to check if your Kindle is affected or not but doesn't say when this is going to happen, just "soon." So I ordered the latest generation Paperwhite but of course the cover with the nice magnet-closer on it that I use for my old Kindle won't fit the new one, oh no, of course not, so there's another purchase, sigh. If you do decide to get a new Kindle and cover, there are a lot of sellers other than Amazon that make nice covers a lot cheaper.

My husband had to replace his phone because of the switch to 4G.  As for Kindle, I installed the app on my phone and read ebooks that way.