Pradis is the Bible Software package created by Christian publishing giant Zondervan. Zondervan feels very strongly that having it's own software package is a huge plus. In fact, a chart available on the Pradis website that compares itself with competing products lists a "Publisher Developed Software Engine" as an advantage that none of the other products have.
However, there are many who would argue that this scenario is actually bad for Bible software. While most publishers will license versions of its books for multiple Bible software packages, Zondervan is often unwilling to do so, keepiing its best sellers to itself. Conversely, many publishers will not license their works to Zondervan, meaning Pradis is overstuffed with Zondervan-only titles. Finally, while numerous efforts to standardize on a specific electronic format for books so they can be used across multiple packages have failed, publisher-locked software makes this dream even harder to realize.