In the context of this keyword, “us” might indicate:

A powerful video editor. - Premium Stock Assets: Gain access to millions of high-quality photos, videos, vectors, and audio files, Google Play

Using www cat3moveus full is straightforward and easy. Here's a step-by-step guide:

Given the structure of the phrase (an odd mix of "cat," "move," "us," and "full"), it is highly likely that this is one of the following: