The Chinese phone upstart that is taking a bite out of gadget maker Apple's market in China is keeping up its impressive start in Singapore, its first market outside Greater China.

On Thursday, Chinese phone maker Xiaomi announced it had sold out 5,000 of its Redmi phones in just eight minutes after they went on sale on its website at noon. Its previous batches of phones sold online for the Singapore market had also sold out within minutes.

Thursday marks the first time that Xiaomi had revealed the number of phones it sold, in response to criticism that its popularity here might be more gimmick than real as it did not reveal Singapore sales numbers previously.

Some netizens had said that the Chinese firm might have been hyping up its sales here by releasing very small batches of phones, which can then sell out quickly.

But last week, Xiaomi had said on Facebook that "we've heard your feedback and will be bringing in 5,000 units (of Redmi) this time", adding that there was "more up for grabs".

Xiaomi's phones have proven to be a hit in their home country as they are seen to be value for money. The $169 Redmi, for instance, has a quad-core processor and a high-definition 720p 4.7-inch screen better than that of many smartphones of similar price points.

In China, Taiwan and Hong Kong, the only other markets where Xiaomi's phones are officially sold for now, the company would usually indicate the number of phones it sold out.

Xiaomi, which plans to make Singapore a base for the South-east Asia market, is known for its preference for small launches. For its initial mainland launch last year, it put on sale just 10,000 units in Hong Kong and 50,000 for the rest of China.

It's hard to compare how well Xiaomi's phones have sold here compared with handsets from its rivals Apple or Samsung as both do not typically release sales figures. But for a rough gauge, when SingTel started selling Apple's iPhone 3G in 2008, the operator said it sold more than 20,000 sets within three weeks of launch.