What are some resources for getting started with meteor. Being able to build a chat apps like these seems powerful.
Discover Meteor has some more; they were giving their book away
(see https://www.discovermeteor.com/blog/we-made-our-book-free/ -- first 4 chapters are free).
That may be enough for the basics. Then look at telescope, or one of the chat apps listed here or search on github. Also plenty of conference talks on youtube.