Apprenticeship is just that:

I had apprentices when I worked in Germany as the Chief Executive in a manufacturing plant.  When you become an apprentice as a person who is going to spend your life working with iron and steel, the first thing you must learn is how steel behaves.  Certainly you can read about it, get fancy diagnostic instruments to test for tensile strength and such, check it's carbon content by using a carborundum wheel and counting the spark content.  That would be one way. 

The way it's done is Germany is you take a raw piece of metal and drag another piece over the top of it to see how it reacts.  Scratches.  How different grades react to different abrasions.  Then you take a flat (bastard) file and begin to file several different samples of iron and steel to get a feel for how is resists or complies with the metal working.  Once you can tell a lot about the steel with just a file, you begin beating on them with a hammer, then under heat.  Etc.  You learn all you must know before you are moved up to welding, turning. forging, forming, smithing and such. You learn to do it by hand first...then with instruments.

There is a problem in our work force.  We do not train or learn the basics of certain skill sets before we place in people's hands the shortcuts to make it easier.  I point in particular to things like Quick books, Graphic Design, Website Management and a plethora of other "tools" that in the hands of the incompetent only allow people to produce more and higher stacks of paper without meaning.

The internet has made researech skill using library cards a lost art.  No one even knows how to farm a telephone book any more.  There are apps for that.  People can publish anything on Facebook or a  blog without a smidgen of necessity for the execution of the english language at any level. 

Unless you learned to write by hand in a notebook and read it back, you are not a writer.  Unless you leaned to keep a set of books in paper ledger books you are dangerous with Quickbooks.  Unless you long ago learned the basics of design on paper by hand, a graphic package for you is a detriment.  IF you don't know how to dig thru a cardex by hand, Google will dead end you.  WE have too much schlock in the world done by people who never learned to drag a bastard file over  a cold hard piece of steel.

Skill is lost... perhaps forever.  But  "there's an app for that"... the worst words in the world.  There is no app for being an apprentice.