Phone "last seen" on WhatsApp after it was lost - how is that possible? I recently lost my cell phone. The following has happened:


At 6 PM I used it for the last time. I sent a WhatsApp message, and I asume I left WhatsApp open.
At 8 PM I realized the phone was gone.
Strangely enough, at 9 PM I was "last seen" on WhatsApp, according to multiple friends I have as contacts.


How can this bee, when my phone is protected with a six digit pin code? I see two possibilities:


Someone has stolen or found my phone. But how could they get past the pin code? Is it possible to bypass for someone in the business of stealing cell phones?
WhatsApp has for some reason registered me as online even though the phone has been in sleep mode (or whatever you call it when the screen is black but the phone is not turned on).


Which of these two is the more plausible? Is there a third possibility?
I found my phone again - I had just misplaced it. I can be very sure that no one touched it while it was lost. I therefore conclude that WhatsApp can indeed register you as "last seen" even though the phone is just in sleep mode.