Hi! It's a little late reply but, as far as I know, there are several apps on the Google Play Store that can add a timestamp to your videos. An app like "Timestamp Camera Free" should serve your purpose.
It allows you to add the current date and time while you're recording videos. It's customizable too, so you can position the timestamp in the corner like you want.
Not sure it's compatible with your Android 4.4 KitKat tho. Should be