Hi,
I am new to digiKam and KDE in general(I am also a novice in UNIX/LINUX).

Like most of you I have several Gigs of pictures and unfortunately they are not very well organised at the moment. Hence comes in digiKam, or atleast I am hoping to. Almost all of these are stored on my QNAP NAS.

I have a macOS, iOS, Android and Windows 10, devices that I would like to be able to get to these photos. While general access is available, I am currently using mostly my Mac as my workhorse. So for now the digiKam is installed on Mac. However in future my workhorse could change and I would not like to start over is and when that happens.

So I am looking for general guidelines on setting this up with flexibility in mind.
Do you suggest to

1) Install digikam, with database local to MAC? In which case can the database be migrated cross platform too?

2) Install digikam and have the database be on the NAS too? Can this database be accesses by other digikam installations in future, probably a different OS

For the first option, I tried with SQLIte and seems having trouble getting all the albums from the NAS. So I am trying to sort this out but seems like I will have to cleanup and start over.

Are there reference forum topics, blogs or articles that you guys recommend to read and implement?

From my perspective, installing your data on Nas will be the best option. This is because it's better and more accessible software to use than what alternative devices on the market offer. I mean, this is what I personally prefer. I am using a Nas device for quite a while, and I am satisfied with it. I bought it from https://prizedreviews.com/best-nas-for-plex/ two months ago, and since then, I have never had a problem with it. But, of course, this is my opinion, so in the end, you decide what option will work better for you.