China's best-selling tablet computer iPad saw its shipments to the country between April and June drastically halved from the previous quarter as Apple Inc's competitors, both international and Chinese, build up market share.

Shipments of the tablet in China were down from about 3.04 million in the first quarter of the year to 1.48 million units in the second quarter, with its market share in the country shrinking from 49 percent to 28 percent during the same period, according to statistics from International Data Corp, a global market intelligence firm.

Apple's product is still No 1 in terms of market share in China's tablet computer sector but rapidly increasing sales numbers from rivals have led to a more challenging market for it.