You being puzzled confuses me, you might as well ask
... doing your taxes is as simple as filling out a form - why would you ever need an online system if I can just grab the form from the newsagent and fill it out? I've personally never had any problems
... we used to get just fine between locations using boats, why did anyone bother to invent planes? I personally have plenty of time to sit on a boat
The difference between travelling with and without apps is nowhere near the differences in the scenarios you are painting.
Airline travel was designed pre-app era. Which means that, by definition, nobody needs smartphones with apps to travel. Airports are probably the most efficient buildings in the world.
... doing your taxes is as simple as filling out a form - why would you ever need an online system if I can just grab the form from the newsagent and fill it out? I've personally never had any problems
... we used to get just fine between locations using boats, why did anyone bother to invent planes? I personally have plenty of time to sit on a boat