Development environment and graphics library The development used the Eclipse IDE, which is the most common environment for the Android Software Development Kit (SDK) [18] and provides facilities for writing, testing and debugging Android applications, this includes integration with the Android emulator and Android devices. Android applications use the Java programming language, compiled for the Dalvik virtual machine. Several graphics libraries, GraphView [19], AFreeChart [20], and AChartEngine [21] were evaluated through prototypes. The demonstration using GraphView was sluggish on a Nexus 7 tablet, but both AFreeChart and AChartEngine provided appropriate facilities and performed adequately on the Nexus 7, a Kindle Fire, and an Android phone.