The smartphone market share
Understanding the market share will give us a clear picture about what cyber criminals are after and also what could be potentially targeted. The mobile application developers can propose and publish their applications on the stores, being rewarded by a revenue sharing of the selling price.
The following screenshot referenced from www.idc.com provides us with the overall smartphone OS market, 2015:
Since mobile applications are platform-specific, a majority of software vendors are forced to develop the applications for all the available operating systems.
The android operating system
Android is an open source Linux-based operating system for mobile devices (smartphones and tablet computers). It was developed by the Open Handset Alliance, which was led by Google and other companies. Android OS is Linux-based, and it can be programmed in C/C++, but most of the application development is done in Java (Java access to C libraries via JNI, short for Java Native Interface).
The iPhone operating system (iOS)
iOS was developed by Apple Inc. It was originally released in 2007 for the iPhone, iPod Touch, and Apple TV. Apple's mobile version of the OS X operating system used in Apple computers is iOS. BSD (short for Berkeley Software Distribution) is Unix-based and can be programmed in the Objective C and Swift languages.