At a time when ever-rising smartphone sales are driven as much by demand for devices that run must-have third-party apps as by the quality of traditional voice and data services, there is a myriad of challenges facing the software developer who is looking to choose which mobile development software platform to invest in. Written from the perspective of an established consumer bank that is about to commence development on its first downloadable application for mobile devices, the case surveys the state of the smartphone market in 2010 and considers the challenges of a platform landscape that includes significantly varying installed device base sizes, growth rates, application distribution models, and hardware device profiles. Focusing on Apple's market-leading iOS platform and App Store, for iPhones and other devices and on Google's developing Android OS and associated Android Market, the case considers potential benefits and pitfalls of each and touches on the reasons that other longer-standing platforms, such as RIM's BlackBerry platform, are less appealing to modern-day application developers.