The rise of Chinese smartphone maker OnePlus has been impressive, and today it has revealed that is has sold more than 500,000 OnePlus One handsets since it was first announced in April this year.

The figure was revealed in an interview with Forbes, and the company’s co-founder Carl Pei said there’s now a stretch goal of one million units before the end of the year.

Perhaps more impressive than the sales numbers of the fledgling device maker is the fact that all of this has been achieved on a marketing budget of just $300 – all of which was spent experimenting with different types of Facebook ads. “We found that we’ve now reached a critical mass of users, and they are helping us spread the word organically,” Pei said.

However, while its handsets are selling faster than the company can make them, Pei also revealed that OnePlus was making less than $10 profit on each device. As such, maintaining this high volume of sales will be critical to enable the company to grow and expand its product line.

➤ OnePlus’ Smartphones Sell Strongly, 2014 Aim Is One Million Handsets [Via Engadget]