Answer
This is a hands-on demonstration. Try this with your friends, and be prepared to explain the physics of the demonstration to them.
Work Step by Step
The light rays that are reflected from a soap bubble that go to you, and those that go to your friend, are slightly displaced. They reflect from the bubbles in different places and at different angles. Different colors will cancel, which produces different interference colors.
Figure 29.26 is helpful. An eye located at a different place will receive different rays and colors.