Widgets exist to offer quick access to certain features in the apps we use most. On the Samsung Galaxy Note 4, home screen widgets let me do pretty much anything, from checking the forecast to browsing my emails.
Ideas can be a fleeting thought, just like a shooting star that appears and disappears within a brief moment. So when you're inspired and have an awesome idea, it's important to jot it down as soon as possible, otherwise it may vanish from your memory for good.
Most new Android devices come with at least one feature that helps control navigation, music, and more through voice-controlled, hands-free communication. While they usually don't end up being completely "hands-free," these apps do stop people from using both hands to perform tasks on their smartphones while driving, therefore distracting them less overall.