I'm not sure how it works on stock android, but afaik, on stock KK sense 5.5 you can only view missed calls, sms, calender etc.
Theres no native support for WhatsApp, Skype, Hangouts etc on lockscreen which sucks. I wish Google would integrate this or work with them to integrate this. I think you can do it using DashClock widgets or something.
I have considered getting the next iPhone partly because of this feature.
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