Can I see if someone is online on Twitter?

[Patrick]

I want to get someone's attention on twitter so I want to tweet her when she is online and/or tweeting herself. Is there anyway I can see if a person on twitter is currently logged on?

[Bibek]

Dear friend, i don't think that we can see if someone is online on twitter as their is no chat system on twitter if you want to get attention of her than you can find her on facebook and send her friend request and than you will be able to know weather she is online or not.