Q.What kind of crabapple am I looking for
My parents used to have a crabapple tree in the backyard (many years ago – 70’s) with white flowers in spring. It had small green fruit in the summer (1/4″ to 3/8″). Here’s the kicker. In the fall, the fruit turned red and soft without a frost. Birds went nuts over them because it was the only soft berry tree in the fall. Our cars were covered in purple bird crap every fall, but it was good to see the birds fill up before their migration. What kind of crabapple was it? Is it some odd cross between a crabapple and chokecherry? The tree was taken down 10 years ago.
Here is a link that provides many varieties and their characteristics.
You will want to find a variety hardy to your growing zone and conditions.
A little research will yield you a tree that will be enjoyed by you and the birds.
https://extension.colostate.edu/pubs/garden/07424.html
https://www.gardeningknowhow.com/ornamental/trees/crabapple/flowering-crabapple-trees.htm