All images exceeding 16MP and videos exceeding 1080p will automatically be compressed to that size or lower. Meaning high-res images and videos won't work with the unlimited storage option.
Integration across devices works really well, it even handles new photos and edits being made on different devices; version control and image processing is excellent.
Google Photos comes with free storage for images up to 16GB and videos up to 1080p which means that most users need no longer worry about storage space.
Any images taken with your phone can automatically be backed up to Google Photos. And the first time you run the mobile app it will also help you back up any existing images and videos you might have on your phone.
While there's a free unlimited storage plan, it's limited to 16 megapixel images and 1080p videos. Uploading full-resolution content, if you opt out of free unlimited storage plan, is limited to 15GB that comes with a Google account which is shared across all Google services. Increasing that storage space costs about $10/mo per 1TB of storage.
Google has a tendency to quickly shut down or abandon services that don't perform well. Google Photos might run the risk of being discontinued if the user base of the app doesn't meet certain criteria.
In addition to folders and albums the app allows images to be tagged, rated and favorited. It also offers the option to create smart galleries (automatically sort photos into galleries) and browse images based on location.
The app analyzes all images that are stored in the app looking to determine which are the most important to you. It then puts those images in collections called Moments that are then prominently displayed within the app.