Utilize the input text as a context reference, choose the right relationship between share and Windows from the options. Options: product/material produced, manufacturer, distributed by, industry, position held, original broadcaster, owned by, founded by, distribution format, headquarters location, stock exchange, currency, parent organization, chief executive officer, director/manager, owner of, operator, member of, employer, chairperson, platform, subsidiary, legal form, publisher, developer, brand, business division, location of formation, creator.

Windows faces intense competition from Apple's iOS and Google's Android, which have cornered the lion's share of the mobile market.

Answer: platform