Portable clocks in the form of wristwatches, but more commonly, pocket watches, became popular in the 19th century when they could finally be mass-produced and marketed. The practicality of the wristwatch became apparent, and by the 20th century, it was the most common watch on sale.The next big leap was the invention of the Quartz watch, which is the design used today by Casio watches.
Portable clocks in the form of wristwatches, but more commonly, pocket watches, became popular in the 19th century when they could finally be mass-produced and marketed. The practicality of the wristwatch became apparent, and by the 20th century, it was the most common watch on sale.The next big leap was the invention of the Quartz watch, which is the design used today by Casio watches.