The video is cute and I like maps too, but a real GPS (i.e. not a cellphone) has never let me down.

Seriously, (moving slightly away from the light-hearted nature of this thread) within its limitations a map is fairly reliable. However, a map is only a reference tool, you still need to do a little bit of that navigation thingy relating the real world to the map to find yourself on the map. This can be easy or difficult depending on terrain and how often you refer to the map app to keep yourself found. A decent compass is sometimes a required companion to a map, sometimes the map is all you need (but keep the compass handy). Knowledge of how to relate real world to the map is a learned skill and not something you intuitively know how to do (although some will disagree).

For a navigator at sea, relating the real world to the map can be very difficult at times. In a previous age before GPS other aids to navigation such as LORAN and Omega were used along with celestial navigation and Dead Reckoning which is almost an art form, and requires skill and practice. (going back to an even older age, celestial nav and Dead Reckoning was it, besides that look-out at the top of the mast).

A GPS has limitations too, primary being that it needs a power source (AA/AAA/rechargeable batteries), but other than that a decent receiver can pinpoint your location with 10's of feet and gets reasonably close in elevation.

Using all three (map, compass and GPS) navigation is much easier; this is what I do. Sometimes the GPS is never turned on, but it's always there.