Below is the top 50 paid applications in the Reference category(data is pulled from iTunes). We also have a list for the best free reference iPhone apps.

• The Night Sky – iCandi Apps
• Photo Collage HD – the Amazing Pic-Frame & Pic-Collage & Postcards Manager Plus iLoader for Facebook, Twitter and Tumblr Pro – Pro Manager Studio for HD Apps of Photo, Video, Music, Picture, Password, Download, Reader, Browser, Player, Scanner, Editor & Wallpapers
• WolframAlpha – Wolfram Alpha LLC
• Dictionary.com – Dictionary & Thesaurus – No Ads – Dictionary.com, LLC
• iHandy Translator Pro – iHandySoft Inc.
• Slango – Urban Dictionary – SchroederDev LLC
• The Guide – Skyrim Edition – UGW
• Merriam-Webster Dictionary – Premium – Merriam-Webster, Inc.
• Our Daily Bread – RBC Ministries
• World Atlas by National Geographic – National Geographic Society
• Quotes! – Digital Hot Sauce
• iBartender – Kevin Kozan
• AA Pokedex Pro – Double A Games & Apps
• Voice Ask – Sparkling Apps
• Modern Warfare 3 ULTD – Call of Duty MW3 – Game Studio LLC
• Urban Dictionary Definitions with Facebook Connect – Bearded Pony
• Plants vs. Zombies – Super Cheats – Altaf Sayani
• Guide For Where's My Water? – Quang Trinh Hai
• Pokemon Black and White App – Michael Sayman
• iCorps: Pocket Reference – ToneMyxr
• Skyrim Alchemist Guide – Alan Cave
• Animated Knots by Grog – Grog LLC
• All Golden Eggs for Angry Birds and Angry Birds Seasons – SKH Apps
• iMissal Catholic (Mass Reading, Calendar, Lectionary) – Cantcha, Inc.
• T.O.R. Codex – Offblast Softworks
• NEC Quick Reference – Alan Cave
• Skylanders Toy Collector – Cherry Hill Technology, LLC
• Fighter Verses – memorize bible verses / scripture memory – Children Desiring God
• RhymeZone – Datamuse Corporation
• Emoticons+ – Critical Hit Software, LLC
• Black Ops Mystery Box Simulator (for Call of Duty Zombies) – Brass Monkeigh Apps LLC
• SWTOR Skill Build Calculator – Firestorm Interactive
• Battery Boost Pro – Appventions
• MW3 Ultimate Utility (for Modern Warfare 3) – Brass Monkeigh Apps LLC
• Password ABC – Password Safe for iPhone – Pro Manager Studio for HD Apps of Photo, Video, Music, Picture, Password, Download, Reader, Browser, Player, Scanner, Editor & Wallpapers
• BibleReader – Olive Tree Bible Software, Inc
• Thesaurus App – Piet Jonas
• The Hunger Games Companion – Jason S. Rosenblum
• Holy Rosary Audio – HANDECH INTERNATIONAL LIMITED
• AppStart for iPhone – AppAdvice.com
• Guide for Cut the Rope (Ultimate Edition) – Appchik Ltd
• Holy Bible ✝ – Apptures
• iCheatGuide – Mario Galaxy 2 Edition – Kitri Software, LLC
• MW3 Titles Pro – Taylor Pierce
• Ultimate Battery Saver – Malibu Apps
• Bible Promises – ReignDesign
• Call of Duty: Zombies ULTD – Kung Fu Studio,LLC
• iRosary (Catholic Rosary) – Opicury Software
• PokeIndex 5th Gen – for Pokemon Black/White – Silver Moonfire LLC
• iBird Explorer PRO – Mitch Waite Group