WhatsApp CEO Jan Koum has attributed part of the messaging service's growing success to the "s****y" products put out by competitors.

Following the $19bn (£11.3bn) acquisition by Facebook in February, WhatsApp has added 70 million active users and is continuing to add 25 million every month.

WhatsApp announced in a blogpost that the service has over half a billion active users around the world.

"In the last few months, we've grown fastest in countries like Brazil, India, Mexico, and Russia," the blogpost read. Our users are also sharing more than 700 million photos and 100 million videos every single day."

In an interview discussing the milestone, Koum put part of the growth down to the inadequacies of rival messaging services such as Line and KakaoTalk.

"There's not enough money and not enough celebrities in the world to convince people to use a s****y product," Koum told Recode. "People are so savvy these days. People expect a good user experience."

While Line and KakaoTalk have achieved success in Asia, Koum claimed that a "bloated" service that integrated games, music and shopping into the messaging service meant they would not be welcomed on the global market.

Despite his comments, some messaging services have experienced significant growth such as Telegram, the Berlin-based messaging app funded by Pavel Durov, who is often referred to as the Russian Mark Zuckerberg because of his success in social media.

Telegram offers a similar interface to WhatsApp but includes encrypted messaging services not offered by its bigger rival.

Privacy-conscious users of WhatsApp subsequently switched services when Facebook took over, leading to a spike in downloads and saw Telegram's monthly active users surpass 35 million.