The tiny card came with an adapter to allow use in a standard SD card slot, and it worked perfectly in my 5-year-old iMac for downloading the photos and videos

At least THAT product will likely have fewer issues with compatible SDXC cards!

It takes a pretty capable card to handle 4K recording so be sure to get one of the recommended ones

I tried two cards I have, one 16GB and the other 32GB, and both works perfectly with the FDR-

You need to get a sufficiently fast card - not every card works with this camera

There is no View Finder, but with an Android or iPhone version of Sony's PlayMemories Mobile [PMM] app installed on your smartphone or tablet, you can use the latter device(s) as some sort of a view finder as well as to remotely control the action cam, including changing camera modes and settings (you can also purchase the more expensive product bundle that includes Sony's Live View Remote, or purchase just the latter separately; but since I don't have the Live View Remote, I can't comment on it further except to say that I don't have a need for it currently, because I'm able to do everything I want to do just using my Android and the PMM app.)The