These days, people are always "online", but rarely really around. In Fleep, we have taken a slightly different approach to showing someone's activity in Fleep. Instead of online/offline indicators, you can check someone's status with the Last active indicator.
When you take a look at the Members pane in a conversation or click on someone's profile, you will see the Last active information:
Last active shows literally when someone was last active in Fleep - when they last sent or read messages. If it says "Unknown", it means they have switched off their Presence features.
Last active is just one of three Presence features in Fleep. The other two being the writing indicator (1) and the "Seen by" indicators (2):