AppShopper - Mac Apps, Mac App Store, iPad, iPhone and iPod touch app store listings, news, and price drops

AppAddict - AppAddict is an online tool that allows you to download third-party apps on your devices without rooting or jailbreaking your devices.

AppAgg - Application Aggregator

vShare - vShare is an app through which you can download apps, games, wallpapers, and ringtones for your Android and iOS devices.

AlternativeTo - AlternativeTo lets you find apps and software for Windows, Mac, Linux, iPhone, iPad, Android, Android Tablets, Web Apps, Online, Windows Tablets and more by recommending alternatives to apps you already know.

Kuaiyong - Kuaiyong brings features to install free as well as paid apps on Apple devices without jailbreaking them.