NEW YORK (AP) _ Mitchell Kapor, who built Lotus Development Corp. into the world's largest independent maker of personal-computer software, resigned as chairman Thursday at the age of 35, the company said.

Kapor, who founded Lotus in 1982, will remain as a director and consultant during the next year, the Cambridge, Mass.-based company said.

Jim P. Manzi, 34, the company's president and chief executive, will succeed Kapor as chairman while keeping his existing titles.

Kapor released a statement saying, ''This is a natural step in my personal growth and in the evolution of the company. ... It's a good time for me to go on to explore other endeavors.''

He added: ''I have no plans to do anything which conflicts or competes with Lotus' best interest, or with my responsibilities to the company.''

Kapor founded Lotus in April 1982 and served as president until 1984, when he was named chairman and Manzi became president and chief operating officer.

Manzi has gradually assumed responsibility for all company operations and was named chief executive in April, Lotus said.

Lotus' first and biggest success was its 1-2-3 program, an electronic spreadsheet for displaying and manipulating financial information. There are 1.5 million copies in use, making it the best-selling business software ever.

However, the company has had trouble finding another big hit and is perceived by some on Wall Street as a one-product company.

Kapor seems to see himself as a fast-moving entrepreneur and probably did not enjoy the challenges of running Lotus once it got big and slowed down, said Kathy Porteus, president of Strand Research Associates in Centerville, Mass., a high-technology research and consulting firm.

''This is what happens with a lot of the entrepreneurs who start a company. It's always a problem to bring it from its growth stage to its mature stage,'' she said.

Kapor declined to be interviewed about his resignation before Friday.

Lotus had net income of $11.4 million in its first fiscal quarter, up 18 percent from $9.6 million a year earlier. Revenue was $69.3 million, up 55 percent from $44.7 million a year earlier.

''Mitchell's contributions go far beyond setting the foundation for a remarkable company success story,'' Manzi said in a statement. ''He contributed a product which has fundamentally changed the way many people do business, and created a platform for a series of products and services that will continue to improve business productivity.''