The top row of the Timeline in your KineMaster video project is reserved for Primary media. Primary media has special tools and properties that layers do not. Images, background fills, and videos in the Primary Timeline support transitions, the speed control tool, Clip Graphics, and can be vignetted.
To add videos and images to the Primary Timeline, tap the Media button. Then, navigate to the folder where your media is located. Tap on it to place it into the Primary Timeline.
When there are two or more videos, images, or background colors in the Primary row of the Timeline, a transition button will appear between them. This button allows you to add a transition between the two clips. Tap the button to open the Transitions panel.
KineMaster comes with some transitions pre-installed. You can download many, many more from the KineMaster Asset Store. Tap the Asset Store button to browse the different transitions and download the one that best fits your project.
Tap any video, image, or background on the Primary Timeline row to open the Options Panel. This provides access to all of the tools that can be used on Primary Timeline media.