I currently have a problem that my grandparents have an old Mac Mini (2007 or so) which is no longer fit for use. They generally just use an iPad now for all of their internetting/computing needs, however they have an abundance of files on their Mini that they want to keep, mainly photos.
I have suggested using cloud storage for it all, but they don't want to do that as they don't want to pay the fee they would need to for the amount of files they have. Also being old, they don't want all their files on the cloud and educating them otherwise is futile.
I have since moved all their files to my more recent iMac for the time being until I can sort something more permanent for them.
I'm looking for a physical storage device that can plug into both my iMac so I can transfer the files to it, and then plug into my grandparent's iPad, so they can view/open their files (photos and word docs occasional audio file) on their iPad.
I recently bought this: https://www.amazon.co.uk/gp/product/B08G8HTR8T/ref=ppx_yo_dt_b_asin_title_o00_s00?ie=UTF8&psc=1 and they insist you download an App, called "CooDisk" which looked like a piece of rubbish! -- also the device didn't work when plugged into the iMac. And so I am returning it, I don't want to go off and buy a more expensive version of the same thing without someone recommending that it will do what I want it to do.
iMac (Retina 5K, 27-inch, 2017)
Is there such a device or even a completely new strategy that I can pursue to achieve what I need to above?