Outside of games, very few apps are doing anything interesting. The only reason for them to be apps at all seems to be to get a place on your Home Screen and to push notifications.
A website in your phone browser will not be able to see when you're leaving work (or a friend's house, vacation), calculate when you will be home, turn on your HVAC, raise your garage door, and unlock your door as you approach the door.
It also won't display the weather for the next few hours and your calendar on the same screen whenever you open up your phone without being an extremely bothersome action every time.
It also won't display the weather for the next few hours and your calendar on the same screen whenever you open up your phone without being an extremely bothersome action every time.