چاکر به معنی بنده و غلام و خدمتگزار است

 یعنی متشکر و ارادتمندم

Equivalent to: Yours sincerely! or Yours truly!

@wesley

This word is somewhat hypocritical and some people like it, but some do not like it. But most of people don't like it to use.

من چاکرتم = I am menial of you.

چاکرتم اکثرا در جواب تشکر یا تمجید داده می شه.

مثلا یکی می گه خیلی باحالی

تو هم در جواب می گی چاکرتم 

You should be careful! It is totally informal and it's usually used among friends and close people. 

It's kind of same as 'thanks' in terms of meaning.

For example:

A:You're cool

B: thanks (چاکرتم)