I use OneDrive for the auto-upload feature. I know it’s not selfhosted, but I want an off-site copy of my pictures anyway, and the phone app works really well for auto-uploading. I had previously tried Nextcloud’s auto-upload, but many times the uploading was stuck and I had to fix it manually.

I then have nightly rclone jobs to download the photos from OneDrive and store them locally. To view them locally, I use Photoview, which works really well with an existing directory structure.