new conclusion

docs/posts/post-XX-how-to-use-arjs-with-aframe.md

@@ -242,7 +242,15 @@ TODO to complete
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 # Conclusion
-TODO
+In this post we have seen how to do efficient Augmented Reality with AR.js, and how to add it to your A-Frame project. 
+We now know how to customize content in AR and make it more personal. 
+We've also learned that it's possible to create your own marker with an easy-to-use marker generator.
+Finally, we've learned how to handle the camera and use multiple distinct markers. 
+This is a lot! Congrats on getting to the end without quitting ;)
+
+I hope you all start creating amazing things with AR.js and A-Frame. Don't forget it's open source, so your imagination is the limit! 
+
+Thanks for reading. Cheers!