aprobify.

Founder and Editor

Fernando Aguilera

I am a developer, not a driving instructor. I built the first version of Aprobify in 2024 after sitting my own theory test in Spain and noticing that every app I tried would tell me which answer was right and none of them would tell me why.

That is the whole product. The California version applies the same idea to the California Driver's Handbook (DL 600): 1,980 questions, each one carrying the section of the handbook its answer comes from, and 1044 road signs indexed by their MUTCD code so you can look up the exact one you saw on the road.

Why the sourcing matters to me

Study material for a driving test is content with consequences. Someone reads it, believes it, and then drives. Getting a figure wrong is not a typo — it teaches a rule that does not exist.

So the rule I work by is that nothing gets published on a claim I cannot point at a source for. In Spain that source is the BOE; here it is the handbook and the MUTCD. When the two disagree with something I remembered, the source wins — that has happened more than once.

What I work on here

  • · Writing and editing the California study material against DL 600.
  • · The sign catalogue, indexed by MUTCD designation.
  • · The automated checks that catch content errors before they are published.

Found something wrong?

Tell me which page and what the handbook says instead. Corrections to published content get priority over anything else I am doing.

hola@aprobify.es

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