[BradyLS]

So, what would Phobos appear like to observers watching its transit every day? Would it appear like a star in the sky? could you even see it?

[petuniasevan]

You'd still see it, but it would appear only 20% of the size of Earth's moon. Plus it is irregular in shape so its phases would appear strange. Its albedo is very low; Earth's moon reflects twice as much light. Still, it would be obvious even to a casual observer.