Google Photos, PhotoPrism, Simple Gallery, digiKam, Piwigo, ACDSee Photo Studio, Flickr, Shotwell, Synology Photo Station, Lychee, Lutim, Synology Moments, Immich, ente Photos, jAlbum, Zenphoto, Piktures, Lomorage, Damselfly, MediaGoblin, Floral, Phimp.me, JCDSee Web Photo Gallery, Memoria, Gallery Revival are some alternatives to Nextcloud Photos.