Breakdown of Twitter Profile Bookmarklet http://davebradford.com/blog/twitter-profile-bookmarklet/

bookmarklet-twitter-profie-ios

javascript:

// Take the current page URL and put it in a variable called url
var url = document.URL; 

// Create a new variable called tweetbotProfile and replace the mobile twitter url with the Tweetbot x-callback-url scheme
var tweetbotProfile = url.replace("https://mobile.twitter.com/","tweetbot:///user_profile/");

// Go to the new URL in tweetbotProfile
window.location = tweetbotProfile;

// To get this to work using Twitterrific just change the tweetbot:///user_profile/ to twitterrific:///profile?screen_name=
// Enjoy!

I'm probably the 100th person to do this and tell you (sorry if that's the case) I made a version that works for both regular twitter and mobile twitter using a regex for the replace. You can see my forked version here: https://gist.github.com/ebetancourt/9744723

Here's an alternative version I've been using for a while. It's a bit simpler, and also works with either mobile or regular twitter.com (in fact, the host name is irrelevant.) Note that even while viewing a specific tweet, the way Tweetbot handles the request it will still go straight to the relevant profile page.

javascript:window.location='tweetbot:///user_profile'+location.pathname

I made a version opens the specific tweet that you are viewing. If you're viewing a profile, it goes to the profile. Also works with either mobile or regular twitter url. But it's a bit longer.
https://yous.be/2014/03/27/twitter-link-bookmarklet/