The new Photos app was designed not only to replace i Photo and Aperture, but also to play better with the photos and videos people have captured on their i Phones and i Pads.
That means that the editing tools are the same, and that your edits carry over no matter what device you're on, the same way Apple's handled some of its i Cloud syncing in i Work office apps like Pages and Keynote.
i Photo is very much easier to handle for making a slideshow.
This software comes with some pre-installed themes for slideshows, and you can add photos to them to have the slideshow prepared.
There was another update released for Aperture as well.
The Aperture 3.4.4 update also has some improved Photo Stream features, along with several bug fixes.
You could then type a name for the new created slideshow under SLIDESHOW category.
Photos is a free upgrade as part of OS X Yosemite’s 10.10.3 upgrade, available through the App Store application.
The upgrade requires OS X v10.6.8 or later, 2GB of memory, and at least 8GB of available storage.
Apple just released a new software update for its popular i Photo app today.
i Photo 9.4.3 contains bug fixes, along with some new features for Photo Stream, like the ability to delete photos by dragging to Trash, and exporting Photo Stream photos through the File Menu.