I created a Twitter App in order to control a specified account (post tweet, etc).
I created this app with my personal account so I can only post tweets on my personal account.
I'd like to share permissions with my other account so I can tweet on it.
I heard about OAuth but I don't understand how to use it.
You can use twurl to authenticate to another account. The account token and secret will be stored in the .twurlrc file in your home directory, you can use those to post from another account.
How to Access Twitter App with another account?