RubyMine is a pretty nice tool for.. as you can see, ruby Development. It based on IntellJ, it is cross platform, it is highly configurable, and it has lots of plugin coming along.

The first thing after getting it installed is to setup the plguins. There is only one plugin that I need – the vim plugin. Just go to preference -> plugin then you can search & install the Vim plugin. However, if you are using Mac, you will need to manually disable the PressAndHold feature of Mac (it is a feature that, when you press and hold certain key, it will show you a list of other possible characters related to that key you have pressed), with the following command typed directly into terminal:

defaults write -g ApplePressAndHoldEnabled -bool false

Then restart your OS, and the PressAndHold would be then disabled.

There are quite a lot of other tips to use RubyMine, to be filled :)