update readme with file viewer section

README.md

@@ -13,11 +13,17 @@ Steps to make changes to remote git repo (tested with github):
 
 1. clone repo using `git clone` (using https url),
 2. cd to directory,
-3. edit file using `vi` (TODO: add emacs command using ymacs),
+3. edit file using `vi` or `emacs`,
 4. use `git login` and put your credentials (user/pass is for push and the rest is for commit),
 5. use `git commit -am "message"` or `git add -A` then `git commit -m "<MESSAGE>"`,
 6. use `git push` to push your changes to remote.
 
+### Web app viewer
+
+If you're working on web app you can open it from browser just prefix the path with `__browserfs__` the app
+is using service worker to serve files from browser fs. So if you clone this repo you will be able to view the local file
+using [https://jcubic.github.io/git/__browserfs__/git/index.html](https://jcubic.github.io/git/__browserfs__/git/index.html).
+
 ### Contributors
 
 To see list of contributors you can check [credits command](https://jcubic.github.io/git/#[[0,1,"credits"]]).