If you've ever used a point-and-shoot camera, the feature should sound pretty familiar: different scene modes and photo settings depending on what you're shooting. So, one each for fireworks, foliage, pets, skies, snow, sports and others, as SlashGear notes. There's even one for documents.
The "smart" in its name suggests that maybe machine learning will play a role here as well, potentially analyzing the scene for you and picking the best settings. This might not use machine learning to improve photography a la what Google does with the Pixel, but it could make Apple's woefully basic camera app a little more full featured.
Whether this will be exclusive to Apple's next round of mobile hardware -- whenever it's announced -- or if it'll apply to legacy handsets too is hard to tell.