The email ecosystem is changing in recent years but yeah, it’s best to expect that there is at least one opportunity for any given email to be sent over the internet unencrypted. MTA-STS has been slowly changing the landscape but adoption isn’t going all that great.
Acts as access point, if you connect to it from another device you get access to stuff on the SD card (via app or built-in webserver)… at least in theory. Quality varies.