I am making an app which has both FB and Twitter connect, With facebook it was very easy but twitter documentation itself is simply frustrating, Maybe someone has come across this? 

I managed to fetch twitter profile image but it's small, I am completely aware of this:

<https://dev.twitter.com/docs/user-profile-images-and-banners>

However, I was wondering if it's possible to get a custom size photo, Some people told me that they have seen it done though no clue on how to do it. If someone could point me to the right direction, I would greatly appreciate it. 

EDIT:
I see my question was not clear enough. I wanted to ask if it is possible to get a custom sized photo just as with facebook API. 

Let me rephrase the question:
Is anyone aware of the twitter profile image size (the original one). From what I have checked myself it seems they are all 400x400px. 

There's no problem of checking the dimensions but if lots of profile images end up being of a different size - then I would rather not have this functionality at all and let users add their own image in my app. 

It might as well be that this "custom sized profile image" is a myth.