Fortnite, one of the world's biggest video games, is available as a mobile phone app for the first time in four years.

It's back, via the newly launched Epic Games Store, on Android phones worldwide - including the UK - but is only available for iPhone users in the EU.

This is because EU law requires Apple to allow third-party app stores on its devices - other parts of the world do not have comparable legislation.

The game was removed from mobile devices in 2020 following a payment row between Apple, Epic - who make the game - and Google, which operates Android.

Users must download an alternative app store before they can download Fortnite and the two other Epic games currently available.

Epic admits the process is "lengthy" and blames Apple and Google for "introducing intentionally poor-quality install experiences laden by multiple steps, confusing device settings, and scare screens."

It comes as Fortnite launches its new season based around Marvel's Doctor Doom.

Why is Fortnite only available on iPhones in the EU?

New EU law came into force in March, which means that Apple has to allow alternative app stores on its devices.

However, those laws do not exist in other parts of the world, where apps can only be downloaded from Apple's official App Store.

"Fortnite has been freed on iOS in Europe, thanks to the Digital Markets Act", Epic boss Tim Sweeney said on X.

"Apple continues to block Fortnite from a billion players in the rest of the world, and the battle rages on to restore free market competition."

Apple says this is mainly for security reasons.

However, Epic argues that it means Apple has a monopoly and can charge high rates - up to 30% commission on purchases - to app developers.

Google charges a similar commission when apps are downloaded through its Google Play store.

However, Google does allow alternative app stores on its Android devices.

Fortnite is free to play but makes money by charging players for in-game purchases for items such as new skins or weapons.

It was removed from Apple and Google's app stores in 2020 after Epic Games stopped paying the commission.