Jumping to definition

The default command is :EnDeclaration. Since you’ll likely be using this pretty often it makes sense to remap it. Personally I use:

au FileType scala nnoremap <localleader>df :EnDeclaration<CR>

If you want to open the declaration in a new split instead of the current buffer use :EnDeclarationSplit instead. :EnDeclarationSplit v creates a vertical split.

Open Documentation For Browsing

:EnDocBrowse opens documentation for the element under the cursor in your browser. You can customize which browser is opened.

For more information, use :h ensime.