[IEEE]
The Android platform used for mobile devices can be applied to embedded systems, such as robot control systems. Developers should create applications by using Java language provided by Android SDK for embedded systems operated via Android platforms. However, in many existing embedded systems, developers have written applications for controlling the system by using C language. Android NDK makes it possible for developers to easily reuse such legacy code written in C/C++ languages. In this paper, we show the difference in terms of performance between an Android application using native code library from C source and an Android application using the same algorithm written in Java language only. We conducted an experiment on five parts: JNI communication delay, integer calculation, floating-point calculation, memory access algorithm, and heap memory allocation algorithm. This paper presents a guideline for an effective way to use native code libraries in Android applications.