diff --git a/sample_app.py b/sample_app.py
index d8e622f..93a9ac1 100644
--- a/sample_app.py
+++ b/sample_app.py
@@ -1,15 +1,27 @@
-# This function was automatically generated. When modifying its signature, take care to apply
-# modifications also to the descriptor files in the repository.
+# -----------------
+# Copyright © 2022 ACK Cyfronet AGH, Poland.
+# -----------------
+#
+# Sample function created for demonstration of creating custom applications functionality
+# See also https://docs.cyfronet.pl/display/ISDOC/Creating+Custom+Applications
+
+from numpy import loadtxt
+import matplotlib.pyplot as plt
 
 def main(numbers_file, multiplier):
     """
-    Main function for application: PYTHONSAMPLEAPP
+    Example Python application that reads the given numbers_file and multiplies
+    the content (numbers) by the supplied multiplier
     Arguments:
         numbers_file: path to input file of type 'text_data'
-        multiplier: parameter of type 'INTEGER'
+        multiplier: number by which the array of numbers is multiplied
     Returns:
-        A file named 'multiplied_numbers_plot.png' of type 'image_data' and format 'PNG'
+        A file named 'multiplied_numbers_plot.png' containing a plot of multiplied 
+        numbers.
     """
 
-    # TODO: Put your application code here
-
+    numbers = loadtxt(numbers_file, comments="#", delimiter=",", unpack=False)
+    multiplied_numbers = numbers * multiplier
+    plt.figure()
+    plt.plot(multiplied_numbers)
+    plt.savefig('multiplied_numbers_plot.png')