Tap on your previously added photo or video.

Tap on Add slide.

Choose photos/videos that you want to add and tap on Done. In total you can add up to 6 videos or images. It can be done in most of the templates, though some of them suppose only 1 photo or video.

Here you go! :) Now you have several slides in your project. You can switch between them to edit the one you need.
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