How to drag and drop images from Safari to Photos on iPhone

Open Photos and Safari apps, then the page on Safari that has the image you want to save into your Photos. Press and hold on one image and drag to corner. (image credit: Pocket-lint)
Continue holding that image with one finger then tap on each subsequent image with your other hand. They will automatically create a stack with the first image. (image credit: Pocket-lint)
Once you have all your images selected, use the hand that was tapping the images to load the App Switcher - swipe up or double tap home button, model dependant. (image credit: Pocket-lint)
Tap on the Photos app, which should be next to the Safari app if you opened them one after the other. Once open, release the hold you have on the images. (image credit: Pocket-lint)
The images will automatically upload to your Photos Library. That's it! (image credit: Pocket-lint)