Periscope for Twitter: Everything you need to know about Meerkat's live streaming video rival

Why bother writing out a tweet or a status update about something when you can just film it outright and share it live with whoever is online at the time?

Meerkat is the live-streaming video app that racked up 120,000 users in just two weeks and exploded with popularity at this month's South by Southwest conference in Texas.

But it isn't the only kid on the live-streaming block.

Twitter acquired an app called Periscope earlier this year for around $100 million and unleashed it last week on a video-hungry internet.

Here's everything you need to know about it.

What does it do?

Periscope lets you broadcast live footage, via your smartphone, to any of your Twitter followers who happen to be online at the time.

Similarly, you can view other people's streams as they're recording them. Unlike Vine, there's no time limit on videos. If you're watching a stream, you can tap the screen to send a love heart showing the broadcaster you like their video.

You can also comment on the stream using the smartphone app. Although it works through Twitter, the comments you write will be kept to the video and not posted as tweets.

During broadcasts users can interact with love hearts or comments

What's more, you don't have to be on a smartphone to watch a stream as they can also be accessed through a desktop or laptop browser.

Why would I use it?

Perhaps you notice something, like a street dance, happening on your way home from work. Or you want to show off the atmosphere at the football game you're attending. Either way, Periscope offers a service similar to Snapchat in that it's instant and hinges on a single moment in time.

It could also be used to capture breaking news as it's happing or - as some users seem to be doing - streaming the contents of your own fridge.

How is it different to Meerkat?

The answer is, it's not. Both services offer the chance to watch or broadcast a livestream through Twitter's network. You can comment on the streams as they happen and save them to watch later at your leisure.

Both platforms have ways to help you find streams to watch. Meerkat has its "Leaderboard" while Periscope boasts the "Most Loved" streams.

In Periscope, you'll be able to see if you and a follower are both using the app through the "people" tab. While Meerkat used to offer this, it was abruptly cut short by Twitter which, after all, runs the network Meerkat is reliant on.

For this reason, Periscope has the obvious advantage - it's Twitter's own offering and the social network will do all it can to prioritise it's own baby.

What are the legal implications?

Like any kind of filming, there are going to be legal implications around privacy and copyright. Taking a smartphone into the cinema and broadcasting the film across the internet, for example, would probably not be tolerated.

Similarly, any kind of invasion of privacy would land you in trouble the same way it would if you were filming offline.

Does it cost anything?

At the moment, the app is free to use. However, it's currently only available on iOS devices - iPads and iPhones.

It's likely that an Android-based version will come along at some point though, so don't fret if you've just stumped up for a brand new HTC One M9.