Unfortunately Twitter doesn't have this feature. There are also no third party apps available.
yes as long as they have a photo on there profile but be careful because it might not be who it says it is.
No, there is no way of knowing who views your profile.
There is no tracking program or application for Facebook to see who visits your profile.
There is no way of doing this.
At this time twitter prohibits that motion.
You cant
who is viewing my facebook profile
You cannot see who is viewing your stuff unless they retweet or like any of your tweets.
By going to your profile and clicking on "followers".
Yes.
Go to their profile and click on their profile picture.
Yes, David Henrie has a Twitter account. See the Related Links below for the link to his Twitter profile.
No, unless you put it on your Bio (profile).