China will someday surpass the United States as Apple Corp.\'s No. 1 customer, the company\'s top executive said Friday. On a trip to China to meet with business partners and government officials, Chief Executive Officer Tim Cook said China \"is currently our second largest market.\" However, he added, \"I believe it will become our first. I believe strongly that it will.\" \"We are continuing to invest in retail stores here and will open many more over the next several years. We have some great sites selected, our manufacturing base is here, and we have incredible partners here. So it\'s a very very important country to us,\" he said. CNNMoney reported Friday Cook was scheduled to meet with China Mobile Chairman Xi Guohua in Beijing, but a spokesperson for China Mobile said the two business leaders had made a non-disclosure agreement and would not comment on the discussion. China Mobile is the world\'s largest phone company in terms of subscriptions. But it currently does not carry the iPhone, which is available in China through rival China Unic.