Ángela Ruiz Robles (March 28, 1895 in Villamanín, León – October 27, 1975 in Ferrol, A Coruña) was a Spanish teacher, writer, pioneer and inventor of the mechanical precursor to the electronic book, invented 20 years prior to Michael Hart’s Project Gutenberg, commonly referred to as the true inventor of the e-book, and over half a century before present-day e-books. She received two patents related to her “Mechanical Encyclopedia” (Spanish: la Enciclopedia Mecánica). In 1949, Ruiz was awarded Spanish patent 190,698 for mechanisms with buttons that, when activated and pressed, displayed the learning materials. In her second patent, 276,364, awarded in 1962, she modified the design to remove buttons and instead include rotational reels that presented the subjects and learning materials. (Spanish: la Enciclopedia Mecánica).

As someone deeply caring for her students and passionate about education, Ruiz Robles designed her mechanical encyclopedia to lighten the weight of the books carried by her students, make learning more attractive, and adapt learning materials to the needs of each student. Her device consisted of a series of text and illustrations on reels, all under a sheet of magnifying glass with a light for reading in the dark, and was to incorporate spoken descriptions of each topic. Her device was never put into production but a prototype is in display at the National Museum of Science and Technology in A Coruña.

Ángela Ruiz Robles, also known as "Doña Angelita", was born on March 28, 1895, in Villamanín, León. She was born into a well-off family, as the daughter of Feliciano Ruiz, a pharmacist and Elena Robles, a housewife. She studied to become a teacher at a college in Leon and started her professional career in the capital of the province as an instructor of stenography, typing and commercial accounting between 1915 and 1916. In 1917, her municipal council unanimously named her teacher and director of La Pola de Gordón school, located in León. There, she married her husband, Andrés Grandal, a merchant seaman, and had three daughters, Elena, Elvira, and Maria Carmen.

One year later, in 1918 she moved to Santa Uxía de Mandiá, a small village close to Ferrol, Galicia, where she serve as a teacher until 1928. In 1934 she carried out an important work as manager of the National Girls School Orphanage in Ferrol.

In 1948 she started to work as a teacher at the Ibañez Martín School, became director in 1959 and stayed in the position until her retirement.

Ángela Ruiz Robles lived in a time during and after Spain’s Civil War. In early 20th century Spain, only 25% of the female population knew how to read and write, and the female illiteracy rate was 60% higher than in men. Women were primarily housewives, with most of them hardly having the most basic education. For that reason, Ruiz Robles’ work and accomplishments are that more significant and worthy of being highlighted.

As a person, Ángela Ruiz Robles was well-known and admired for her devotion to her students and for striving to innovate the outdated teaching methods of the time. Throughout her life, all of her books, inventions, and career were centered around making education accessible, easier, and enjoyable for all types of students and all their specific needs. In her spare time, Doña Angelita taught free night lessons to people with fewer resources. She went as far as visiting her students’ homes at the end of the day to ensure they learned and understood class material.

Ruiz Robles died in 1975 in Ferrol. Up until her death, Ruiz Robles paid all her patent fees for her mechanical book.