To quickly add photographs, open the home screen of the app and click on the 'add photographs' button. You can add photographs directly from the gallery of your device or you can do so by taking pictures from the device camera.
To select multiple photographs at a time just tap on them (maximum ten in one go) to select them.
Please note that the sequence of selecting the pictures is important as this is the same sequence in which they will appear in the PDF document when it is created.
After this selection, simply click on 'next' to save them to a new folder or to an existing one!