Steps to Set the Photo Slideshow1. Open "Setting", tap "Photo & Camera" option and you'll find "Slideshow" in the right column of the pane.
2. Tap "Play Each Slide for" option and select the time.
Here you'll find options for 2 seconds, 3 (the default), 5, 10, and 20 seconds.
There are tiny differences between "Slideshow" and "Picture Frame". If you want to play slideshow with songs, you can choose nothing but "Slideshow" because you're allowed to add music when playing slides using "Picture Frame".
After locking the screen, press "Home" and wait for the little flower showing up. Press the flower to launch "Picture Frame". Here provides you the way to setup the speed of slides playback.
Go to Settings > "Picture Frame" > "Show Each Photo For" and set up the time.
Here you can also find options for 2 seconds, 3 (the default), 5, 10, and 20 seconds.
The setting I have mentioned above is not apparent enough to be found on iPad. If you prefer to use iPad as a digital picture frame or frequently use the audio player "Airplay" to make presentations, the method would be quite useful.