I use my Fisher Space Pen almost exclusively. It hasn't let me down.

It has some interface similarities with the Telegram app. (Not sure who was first!)

http://i.imgur.com/fTQjgqa.jpg

403 Forbidden

Well at least it isn't a 503

They deleted it for some reason, but here it is from Google Cache: https://webcache.googleusercontent.com/search?q=cache:http:/...