Be sure tp check out UXRoot's fantastic new app. Also his forum post regarding it.
He doesn't say much in his post about navigation options, so I thought I'd share what I've figured out and put it in a separate post so it wouldn't be too hard to find.
1) When you enter the app or a new location, you will be looking at one side of the street or the other. Clicking the Cross Street button switches back and forth which side of the the street you are looking at. This should be obvious, but it was an embarrassingly long time before I realized it.
2) If you want to look some direction other than directly to one side of the street or the other, you can edit the URL to look in any direction you want. For example, the default URL when you enter the app is: http://www.glitchplace.com/#pano:ApF3jzgMhPVm7Cr46Q_tfg/118. That 118 at the end of the URL is the direction you are looking - 118 degrees, a little south of east. You can edit the URL to replace that 118 with any number (preferably 0 to 359, but anything works), where 0 is due north, 180 due south, etc. Select the 118 in the URL, type in the number you want, hit Enter and you will be looking in the new direction.
3) The only keys that I've found that have actions are:
left and right arrows to walk - the a and d keys don't do anything
space bar to jump
If you walk all the way to one end or the other and hit Enter, you will move to the next frame on the street. So with the arrow keys and Enter you can stroll down the street while looking around.
4) As in Street View, you can also move around by dragging the little Street View Man in the Map Street window at the right of the screen.
That's what I've found so far. Thanks, UXRoot for the great app!