The app stores are arguably the biggest revenue drivers for mobile manufacturers, bringing in more cash (for far less cost) than producing the handsets themselves. Looking at the app store landscape from a bird’s eye view, the infographic below (created by WebpageFX)compares Apple’s App Store (the juggernaut of the bunch) against Android Market (quickly growing into a sizeable beast at a growth rate of over 500%) and BlackBerry App World (with huge reach but low quality apps), together with the Nokia, Windows Phone 7 and Palm app directories.

The most interesting takeaways from the stats below include:

• In terms of quantity alone, the iPhone App Store leads the pack with 375,566 apps. Android is sitting at 224,808 apps. Then comes iPad, Ovi, BlackBerry, Windows Phone 7 and Palm.
• The paid vs free app ratio is 71%/29% on iPhone, 40%/60% on Android and 75%/25% on BlackBerry.
• iPhone users have an average of 48 apps on their phones, Android users have 35 and BlackBerry have 15.
• A total of 14 billion apps have been downloaded across all the app stores since Apple pioneered the app store concept in July 2008.
• Mobile app revenue totalled over $5.2 billion in 2010, and is heading for $15 billion in 2011.