An app in the Mac App Store allows you to edit photos from the Photos app using any editor on your Mac. By installing this app and enabling its extension, you can jump from Photos to an editor of your choice and back again without creating any temporary files or wasting time.
With the Photos app in macOS Sierra you can markup your photos with shapes, text and drawings without leaving the app. You can use this to add to your photos before sharing them. You can revert back to your original at any time.
A very exciting new feature of the Photos app in macOS Sierra is the ability to search your Photos library for objects. For instance, you can search for 'boat' and it will show you pictures in your library that have a boat. Take a look at how this feature works.
The Faces feature in Photos is one of the most useful parts of the app. Once you start using it, it is easy to find photos of the people in your life. You can then access these photos quickly when you need them.
The Photos app uses the term Albums to refer to a grouping of photos that you create. But unlike physical photo albums, you do not create a copy of the photo each time you add it to an album. Only one copy of the photo exists in your library, even through you can place it in as many albums as you like.
You can use Keynote on your Mac to create photo journals by creatively arranging your photos on slides, then adding text and other design elements. You can then share these as view-only slideshows with iCloud.com. Other people can view these even if they do not use Macs or iCloud.
The Photos app makes it easy to crop your pictures. Cropping is non-destructive, so you can always revert to the original. You can create a custom crop or select from specific ratios. You can then export the photo at a specific pixel size if needed.
The Photos app lets you easily identify faces in your photos. You can assign a name and Photos will help you find that person in other pictures. Once you have assigned some faces, you can search for them and view photos that contain those people.
With the Photos app in El Capitan, you can adjust the time and location data for your photos. If you have photos taken with a regular camera, it may not include any location data, and the time can easily be off if you haven't set your camera's time or are traveling in a different time zone. The Photos app makes it easy to go back later and make changes to time and location.
A new feature of Photos in El Capitan allows third-party developers to build extensions. These extensions can add more features to the Photos editing tools and other parts of the Photos app. It is early, so only a few extensions exist, but developer will undoubtedly be adding more soon.
If you want to add some text to a photo, you can do it with the Preview app that comes with your Mac. You can add some large text to create a funny or inspirational image to post to social media. Or, you can add a watermark to protect your images before uploading them to the web.
Learn to use the new Photos app in iOS 7 to find your photos. In addition to the Albums view that was available before, you also have a Photos view that lets you dig into your pictures by year, collection and moments. You can also bring up a map showing the the photos in any sub-division.
For most users the best way to manage photos on an iPhone is to download your Camera Roll photos on to your Mac in iPhoto, treating your Camera Roll like a normal digital camera. Then create albums in iPhoto and sync those back to your iPhone to have a selection of photos to carry with you.