Journalists and legal commentators in England and Wales no longer have to ask permission to tweet, text or email from court.
Previously an application had to be made to the individual judge in a case.
The Lord Chief Justice said new guidance on the use of "text based" media would enable court proceedings to be reported fairly and accurately.
But he said permission could be withdrawn at any time if it interfered with the administration of justice.
Announcing the change, Lord Judge told reporters: "Twitter as much as you like from today."
The guidance clarifies the use of tools such as mobile email, social media including Twitter and internet-enabled laptops in and from courts.
It replaces interim guidance issued last December which left it up to each judge to decide whether electronic devices could be used in their courtroom.
Lord Judge said: "The judge has an overriding responsibility to ensure that proceedings are conducted consistently with the proper administration of justice, and to avoid any improper interference with its processes.
"A fundamental aspect of the proper administration of justice is the principle of open justice.
"Fair and accurate reporting of court proceedings forms part of that principle."
The guidance makes clear that photography in court remains strictly forbidden.
It also emphasises that anyone using electronic text is strictly bound by the existing restrictions on reporting court proceedings under the Contempt of Court Act 1981.
Lord Judge said: "It is presumed that a representative of the media or a legal commentator using live, text-based communications from court does not pose a danger of interference to the proper administration of justice in the individual case.
"This is because the most obvious purpose of permitting the use of live, text-based communications would be to enable the media to produce fair and accurate reports of the proceedings.
"As such, a representative of the media or a legal commentator who wishes to use live, text-based communications from court may do so without making an application to the court."
Lord Judge says equipment should be unobtrusive, hand held and silent and the number of mobile devices in use at any given time may have to be limited if they interfere with a courts own sound systems.
Members of the public will still have to make an application to the judge in a case if they want to use the devices.
In Scotland, the court's permission is required for the use of devices allowing live text-based communication from court.
Scotland's senior judge, the Lord President, Lord Hamilton, said in a statement he had noted the new guidance issued by the Lord Chief Justice.
He said: "I will give full consideration to this guidance and its implications with a view to formulating suitable guidance in Scotland."