Swipe with one finger
Look Around: Touch the screen with one finger and drag to change the view direction. Avoid dragging a selected object.
Swipe with two fingers in parallel
Pan: Touch the screen with two fingers and drag. You will move horizontally in the specified direction.
Pinch with two fingers
Zoom: Pinch with two fingers to zoom out. Increase the distance between the fingers to zoom in.
Pinch with two fingers, then move the fingers around
Orbit: Pinch and then move one or both fingers to orbit around the point between your fingers.
Move two fingers around some point in the 3D view

Rotate an object: Tap on an object to select it. Place a finger on the selected object again, move aside slightly and hold. Place another finger anywhere outside the object and move the finger around to rotate the object.

Holding one finger on the screen, tap on objects with another finger

Select multiple objects: Tap on an object to select it. Place and hold a finger anywhere on the screen (this can also be the selected object). Then tap on other objects that you want to select.