Terrific point by Marco on one of the negatives of catering to the Free crowd.
"Instapaper Free always had worse reviews in iTunes than the paid app. Part of this is that the paid app was better, of course, but a lot of the Free reviews were completely unreasonable.
Only people who buy the paid app — and therefore have no problem paying $5 for an app — can post reviews for it. That filters out a lot of the sorts of customers who will leave unreasonable, incomprehensible, or inflammatory reviews. (It also filters out many people likely to need a lot of support.)
I don't need every customer. I'm primarily in the business of selling a product for money. How much effort do I really want to devote to satisfying people who are unable or extremely unlikely to pay for anything?"