Andrew Kay, the designer of an early portable computer, the Kaypro II, that became a smash hit in the early 1980s before his company fell into bankruptcy in the ’90s as the computer industry leapfrogged ahead of him, died on Aug. 28 in Vista, Calif. He was 95.

His death was confirmed by his son Allan.

For a time, Mr. Kay’s company, Kaypro, was the world’s largest portable computer maker, ranked fourth in the PC industry over all behind IBM, Apple Computer and RadioShack.

Early on, the Kaypro II developed a loyal following. Stephen M. Case, who would become chief executive of America Online, bought one as his first computer, adding a 300-baud modem to explore the fledgling online world.

“The Kaypro computer was a necessary step in getting to the iPad,” Paul Freiberger, co-author of “Fire in the Valley: The Making of the Personal Computer,” said in an interview on Friday. “Back then few thought of making a computer you could carry around. It was loved because he got almost everything right.”