Android KitKat has improved the way to use your phone. Thanks to it you can use widgets on Lockscreen and I was used to use it with my previous phone. I have found how to use it now with Sense 6 on our HTC One M8!
In fact this is only a little option to check on settings. So go to settings and on that go to Security / Enable widgets on lockscreen.
Now you can use widgets on your lockscreen. Just go to lockscreen and slide the screen to left to add some widgets as you see on the video.