In my previous discussion, I posted about using the Pennsylvania Archives. I found that I could also find records on my great great great grandfather who was on the Confederate side. I was lucky that Texas has a great Confederate Pension search, and could find his pension applications, but on Footnote I was able to find other records for him which allowed me to show my grandmother where her great grandfather served in the Civil War.
Also, I find I use the Philadelphia and Washington City Directories, they are especially helpful for 1890, and the years in between census records, sometimes I can determine when a wife became a widow from the directories, or just a moment in time when she was the head of household when her husband may have been in the military when they published the directory.
I, too, find the City Directories useful (in my case, the City is St. Louis), through these directories, I have established that my grandfather lived at the same address when he moved to the city until he died. The census shows he owned the house, now I know that ownership is a fact I can establish. It also raises the question — did he own his home and place of buisness in DeSoto? I will need to search outside of Footnote for those facts, but footnote pointed out the areas for searching.
I use Footnote to upload documents and pictures and store them online. I've also found that their viewer allows me to see them more closely or more clearly. It's also a good place to share the docs and pictures I've found.