iPad vs tablet

iPad

noun
  • A lightweight low-power tablet computer of a particular range from Apple Inc. 

  • Any lightweight low-power tablet computer. 

tablet

noun
  • A tablet computer, a type of portable computer. 

  • A type of round token giving authority for a train to proceed over a single-track line. 

  • A pill; a small, easily swallowed portion of a substance. 

  • A slab of clay, stone or wood used for inscription. 

  • A confection made from sugar, condensed milk and butter, produced in flat slabs, with a grainer texture than fudge. 

  • A short scripture written by the founders of the Bahá'í faith. 

  • A block of several sheets of blank paper that are bound together at the top; pad of paper. 

  • A graphics tablet. 

verb
  • To form (a drug, etc.) into tablets. 

How often have the words iPad and tablet occurred in a corpus of books? (source: Google Ngram Viewer )