Altstore - A home for apps that push the boundaries on iOS
Amazon Appstore - The Amazon Appstore is a place to purchase and download apps for your Android device.
Cydia - An alternative app store for jailbroken devices.
GetJar - Discover and play paid apps and games for free.
iOS Haven - A listing of tweaked apps and games for iOS devices. Install directly from the browser.
AndroidPIT - Android news, apps, reviews, tips, hardware comparisons and forum