This is the gallery app I use. I'd love to use Simple Gallery, but F-Stop has a key feature that Simple doesn't: selecting all the images in one day. It's such a time saver, I couldn't give it up.

Sorry, I accidentally duplicated this post from @Dnew10@lemmy.world.

Not sure if evil or not, but Dropbox also has a nice scanning feature. It goes to the cloud, but you can download the PDFs after creating them. And there is a free tier.