Twitter has rolled out hardware security key support for Android and iPhone devices, to help users keep their accounts more secure.Now anyone with a security key set up on their Twitter account can use that same key to log in from their mobile device, so long as the key is supported.Twitter first announced support for hardware security keys in 2018.The aim was to allow users "to add a physical security barrier to their accounts in place of other two-factor authentication options," reports TechCrunch.Hardware security keys mean hackers cannot easily break into Twitter accounts, even if they have usernames and passwords.The company first allowed hardware security keys to its own staff, after it suffered a massive cybersecurity attack.In total, 130 accounts were targeted by attackers, 45 accounts had Tweets sent by attackers, 36 accounts had the DM inbox accessed and eight accounts had an archive of "Your Twitter Data" downloaded (none of these was verified), informed Twitter.The accounts of major public figures including US Democratic presidential candidate Joe Biden, Barack Obama, Elon Musk, Bill Gates, Jeff Bezos, Apple and Uber were simultaneously hacked by attackers to spread a cryptocurrency scam.