Members range from Oprah, Drake and Kanye West to Elon Musk and Mark Zuckerberg.

The tech billionaires both made made much-covered appearances in its virtual meeting rooms last month, along with investing app Robinhood's CEO, Vladimir Tenev. Just this weekend the Tesla and Space X founder made more noise about the app by Tweeting a public invite to Russian President Vladimir Putin to join him "for a conversation on Clubhouse".

Talk around the app is beginning to reach beyond billionaire founders, CEOs and celebrities, too.

It was launched in March 2020 and by May 2020 it was being valued at $100 million, according to CNN. It is now reportedly valued at around $1 billion following its latest funding round, making it a global player in terms of size.

It has even begun to become entwined with geopolitics. Last Monday Beijing moved to block the app, the Financial Times reported, after it became a rare space for Chinese internet users to discuss sensitive and political subjects free of surveillance. Invites had been advertised for up to $78 apiece ahead of the move.

Here we take a look at this app, its background and investors, and - importantly - how you can join:

What is Clubhouse?

The app, which can only be hosted on iPhone, is a social network/podcasting hybrid. It allows you to hear talks on all kinds of topics in its virtual rooms, which operate a bit like a real-life panel talk or conference - people in the audience are only allowed to talk when they're selected.

Discussions range from how to secure investment in your start-up to cooking, and, like in-person conversations, the talks on the app are not recorded or released. There is no written posting function.

Who founded Clubhouse?

The platform was founded by Paul Davison and Rohan Seth, both of whom had previously worked in the tech start-up world.

The pair met back in 2011 through a friend and "connected over a shared love of social products". In late 2019 they reconnected, and decided to give founding a new app a last shot.

The founders say that in launching Clubhouse, their "goal was to build a social experience that felt more human—where instead of posting, you could gather with other people and talk".

They wrote on their blog: "Our north star was to create something where you could close the app at the end of the session feeling better than you did when you opened it, because you had deepened friendships, met new people and learned."

How do you join Clubhouse?

The app is invite-only, and each new member is only allowed to ask one person to join - a bit like in some traditional members' clubs. But there is no vetting process to go through after being invited, so once you've got that link, you're in (complete with a party popper symbol to indicate you've just arrived).

The app states that you can also request to join and be added to a waiting list, however, so don't worry if you don't know anyone with access.

How big is Clubhouse?

The app has rocketed from having 5,000 members in May 2020 to more than 2 million "weekly active users" today, leading to many comment pieces emerging saying that the exclusive app has gone mainstream.

According to data provider App Annie, nearly 940,000 people installed it in the last week of January alone.

Do you have to pay for Clubhouse?

No. It currently has no adverts or fees, and its founders have said that "our focus now is on opening up Clubhouse to the whole world". In late January the company released a post stating that they're considering implementing paid features, tickets or subscriptions, however, to pay creators for hosting discussions.

Who are Clubhouse's investors?

Clubhouse has publicly stated that as of end January it has 180 investors, including "many members" of the team who were there at the app’s very beginning.

Its most talked-about backer has been venture firm Andreessen Horowitz, which has invested tens of millions of dollars into the platform. The firm, which was founded by US venture capitalists Marc Andreessen and Ben Horowitz, led a reported $100 million fundraising round in January that is said to have valued the start-up at around $1 billion.

Can you get Clubhouse on Android?

Not yet - the app is currently iPhone-only. But its founders say they plan to use some of the new funds raise to begin work on an Android version.

Are there any Clubhouse rivals?

Twitter is reported to be developing a Clubhouse-like voice product called Spaces, which would be hosted within its platform.