[xenophanes]

> For example, iBooks provides a slider UI element to control the brightness level. This puts Apple in an unfair competitive position because other apps — such as the Kindle or even non-competing apps such as Instapaper2 — can’t offer this functionality to their users.

GoodReader has a brightness control built in. Are they not supposed to? Why not?

[lleger]

The point is that the API Apple used to implement it isn't available to developers. GoodReader likely implemented a workaround, such as the one Instapaper has. It's not a native element, however.