How to group pictures together on iPhone?

The simplest way is to make an album in the Photos app. Tap the Albums tab, then the plus icon to create a new album and give it a name, such as "Wedding Guest Photos" or "Ceremony Pics". Then go to your main photo library, tap Select in the top right, and tap every picture you want to include. Once selected, tap the share icon (the square with an arrow) and choose Add to Album, then pick your new album.

If you want to group photos by event or date without moving them, you can also use the search feature to find photos by location or people, then select and add them to an album in the same way. Albums are private unless you share them, so they are a safe way to organise your own collection.

For a quicker method, you can drag and drop photos into an album if you are using an iPad, but on an iPhone the Select and Add to Album route is the most reliable. You can also use Favourites by tapping the heart icon on individual photos, then view them all in the Favourites album. That is handy for picking out your best shots quickly.