Since I am using an iPad to project guided notes onto the screen in my classroom, I can easily record what we're doing simply by turning on the video recording on my iPad (though I do have to remember to do this, which can sometimes be a challenge!)
I did this for the first time a few weeks ago, and my students were initially a little weirded out by the fact that I was recording, but they soon got used to it and don't seem to notice much anymore.
Then, using a free app, I compress the video to a reasonable size and upload it to Canvas, our district's learning management system. I can embed it in a file, and students who were absent or need a review of what we discussed in class can watch it:
I'm always looking for ways to help students take charge of their own learning rather than depending on me, and I hope this will be a useful resource for students who were absent or are struggling.