I had Virtual Pool 1 15yrs ago on my computer and loved it.
A few months ago I downloaded Virtual Pool 3 for my iPod Touch. I didn't like it at all. It was too hard to use. I fooled around with it for a few minutes, then never touched it again. It probably is the best pool game for phones, but it is far short of the computer version.
I understand the author is working on Virtual Pool 4, that will probably address all the usability issues.