Java tutorial
//package com.java2s; import java.io.File; import android.os.Environment; import android.os.StatFs; public class Main { public static long getAvailableInternalRomSize() { File path = Environment.getDataDirectory(); StatFs stat = new StatFs(path.getPath()); long blockSize = stat.getBlockSize(); long totalBlocks = stat.getBlockCount(); long availBlocks = stat.getAvailableBlocks(); return availBlocks * blockSize; } }