Organizations that develop mobile applications are always on the lookout for Software Development Kits (SDKs) to build robust and user friendly mobile apps. Tech Republic published a list of essential SDKs for mobile app development.
iOS official SDK: The iOS official SDK is comprised of 4 development sets: Cocoa Touch, Media, Core Services, and Mac OS X Kernal. Cocoa Touch includes touchscreen support elements; The Media set includes video, audio, photos, and multimedia function compnents. Core Services include networking. Mac OS X Kernal includes essential functions relating to file systems, power management, and security.
Android SDK: The official Android SDK has emulators, development tutorials, libraries, sample code, and detailed documentation.
Windows Phone 8 SDK: This SDK comes with a copy of Visual Studio Express 2012. When Windows 8 becomes mainstream Windows Phone 8 SDK will become more integrated. It has plenty drag-and-drop controls and code chunks.
Snapdragon Android SDK: This SDK includes a number of tools for improving application development on Snapdragon-powered devices. This includes powerful facial recognition technology, sophisticated location services, and surrounds sound recording capabilities.
RhoMobile: RhoMobile is based on Rhodes, an open source cross-platform Rails-based mobile development framework. With RhoMobile, you can build robust applications that can be deployed on just about major mobile operating system. Their platform allows to write code once and deploy the app over multiple operating systems.