diff --git a/README.md b/README.md
index e0f9421..20fb9a4 100644
--- a/README.md
+++ b/README.md
@@ -21,7 +21,8 @@ This is how the display looks like in action:
 
 ### Software
 
-* Arduino IDE 
+* Arduino IDE
+* HR50-Api: [https://git.qrz.is/clemens/hr50-api]
 
 ### Libraries