The icon and name are a first filter. For example, suppose I'm searching for "star chart".

When I see "Horoscope" in the name of a result, I skip it.

When I see the name is "Potty Chart" and the icon consists of a toilet with the seat up and a star hovering over the seat, I skip it.

When I see the name is "iAllowance" and the icon is a piggy bank, I skip it.

When I see the name is "Vinmeen Lite" and the icon shows a constellation, I think "what the heck is a vinmeen" and click. :-) (It turns out it is the Tamil word for "star").

I judge them by screenshots and then icons. It's certainly easier than downloading them all. Ratings on the app store don't tend to be very accurate for my tastes.