The "Pan Tool" is used to move around your sketch. To use it, simply select "Pan" from the tool bar at the top of the screen. Now you can press and hold on the sketching area to move it around. Don't worry about where you touch the screen; you can't modify your sketch while the Pan Tool is active. To go back and make changes to your floorplan, simply select another tool from the toolbar.
Zooming: You can pinch-to-zoom while using the Pan Tool, as well as the select tool.
There is one tool in PhoenixSketch left to discuss: the Interior Wall Tool.