Your facebook's source code has a list of your friends' last active time. "Active time" means online, log in, or seen time. You can search " lastActiveTimes " in your source code of facebook to get a " JSON-object " which is a key-value pairs about facebook id and unix timestamp.This is an online parser, which can parse your facebook source and list the active time in order.
※Please use this app on your own Facebook account. Do not use this app to check Facebook data of other people without permission to avoid legal issue.※