What are some alternatives?
Piwigo - The default home page of a Piwigo photo gallery is the list of root albums. If it doesn't fit your need, you can create your own customized home page. There are 2 main methods: either you create an additional page or your create dynamic blocks.
Flickr - image and video hosting website
Lychee - Lychee is an open-source, free software program for self-hosted photo management. It can be installed on the user's own server or website. The software permits the uploading and management of photos and also makes sharing photos very easy.
Imgur - Imgur is a free and simple image hosting service with image editing feature. Signup is optional.
500px - Connect, get inspired, and grow your skills.
Google Photos - All your photos are backed up safely, organized and labeled automatically, so you can find them fast, and share them how you like.