MPs have been given official approval to tweet updates of debates from the House of Commons, providing they do so "with decorum and regard for others".
There had been some confusion after Deputy Speaker Lindsay Hoyle told MPs in January that they should refrain from using the micro-blogging site while in the chamber.
But a new report released by the Commons Procedure Committee said iPads, as well as the use of smartphones, was allowed.
It said: "The use of Twitter by Members is very popular and its use in the chamber or Westminster Hall has caused comment from Members themselves and from the public.
"Many different views have been expressed, from those who believe that it is a threat to the dignity of parliamentary proceedings to those who argue that it brings Parliament to a whole new audience."
The report added: "Tweeting about proceedings from the galleries is in our view no different in degree from presenters commenting on live broadcasts of proceedings or indeed from tweeting or blogging about proceedings when watched from outside the chamber.
"Whilst tweeting from inside the chamber is clearly a more sensitive matter, we consider that it would be inconsistent to ban this one practice whilst advocating the approach based on decorum rather than activity which we advocate in this report."
The report said 225 MPs now tweet and the committee had received a large number of correspondence during its consultation.
But while the committee said the use of smartphones and iPads was allowed, laptops are still banned.
Devices should be no larger than an "A4 sheet of paper", it said.
But MPs can use devices as an aide memoire during debates and send and receive messages.
The committee said the changes would be given a one-year trial.
It concluded: "Finally, it has to be acknowledged that electronic devices are ubiquitous now in a way that even four years ago was not the case.
"Banning them from the chamber might make the House appear out of touch with modern life and would mean that those in the chamber would be the last to know of breaking news widely available on the internet.
"We therefore conclude that Members should be allowed to use electronic hand-held devices for any purpose when in the chamber whilst not speaking, and that the current ban on the use of hand-held electronic devices as an aide memoire, whilst speaking in a debate, should be ended."
Last week Liberal Democrat MP Gordon Birtwistle (Burnley) was rebuked for using his mobile phone in the Commons.
Getting to his feet during the opposition day debate on fuel prices, Mr Birtwistle clutched the smartphone and, stuttering, thanked Ms Eagle for allowing his intervention.
But as other MPs saw him studying the phone, they began to heckle, leading Mr Birtwistle to stammer: "Could I refer to an email I received ...?"
Before the Lib Dem could finish, Speaker John Bercow told him to sit down, proclaiming "this is not an orderly way to conduct the debate".
Mr Birtwistle apologised but tried to intervene three more times before eventually leaving the chamber.
If the MP was to do the same today, his hesitation may well see him fall foul of the new guidelines as the committee has ruled that phones must only "be used in a way that does not impair decorum".
Former Commons deputy speaker Sir Michael Lord used his maiden speech in the House of Lords tonight to attack as "harmful and disruptive" similar rules which will apply in the Upper House.
Peers earlier this month agreed that devices such as iPads should be allowed in the chamber for a one-year trial period.
Sir Michael, who sits in the House as Lord Framlingham, said: "One of the duties of any generation is to hand on to the next generation that which has been entrusted to its care.
"May I in this context say that I was deeply saddened to see that we have agreed to an experiment to allow the use of electronic devices in this chamber.
"I believe this will be harmful and disruptive and I sincerely hope it will not become a permanent feature."