Earth, moon and sun reading apps dominate the Android Books & Reference App list this week with four apps dedicated to the subject making the Top 10. Knowledge engine WolframAlpha is still the top paid Android Books & Reference app in the Android Market this week. The app has led the list since we started counting at the beginning of May.

To prepare for Mediabistro’s upcoming Publishing App Expo on December 7-8, we will be spotlighting the top grossing book apps every week–helping our readers discover and analyze successful content.

Below, we’ve listed the top ten paid Android Books & Reference apps of the week. We’ve linked to the online pages for the individual apps so you can explore the content.

Top Paid Android Books & Reference Apps

1. WolframAlpha

2. Moon Phase Pro

3. TerraTime

4. Aldiko Book Reader

5. iQuran Pro

6. Moon Reader + Pro

7.  NIV Bible

8. iKamasutra Sex Positions

9. Sundroid Pro

10. LDS Scriptures App