Dead people's text messages, emails and voicemails could be considered a valid will in exceptional circumstances and when a judge approves it if proposals put forward by the Law Commission are adopted.
The independent body, which helps advise ministers on the law, proposed a new power allowing the courts to recognise a will that would not be valid under existing formality rules, but where the will-maker has made clear their intentions.
One example could be the family of a car crash victim - who has not made a formal will but has expressed their intentions in electronic or other messages - applying to a court to have those communications recognised as a formal will.
Those smartphone, tablet or other messages could only then be recognised as a will if a judge approved.
Noting that 40% of people die without making a will, the Law Commission said the "Victorian" rules need updating because they are "out of step with the modern world" and are "failing to protect the vulnerable".
It has launched a consultation on proposals to soften the strict formality rules, a new mental capacity test which takes into account the modern understanding of conditions like dementia, and a suggestion that the age for making a will should be lowered from 18 to 16.
In a consultation document, the Law Commission acknowledged the proposals on electronic communications could cause family arguments or worse but ultimately recommended them.
It said: "We note that the potential recognition of electronic wills via a dispensing power is a double-edged sword.
"On the one hand, it seems essential that the power be applicable to electronic documents.
"Testators (people making a will) who do not follow the formality rules – either through ignorance of them or necessity – are increasingly likely to use electronic means.
"For example, a person who is seriously ill in hospital may have more immediate access to a tablet or smartphone than to a pen and paper, and may be more able to speak than to write.
"On the other hand, the potential recognition of electronic documents could provide a treasure trove for dissatisfied relatives. They may be tempted to sift through a huge number of texts, emails and other records in order to find one that could be put forward as a will on the basis of a dispensing power.
"In that way, the large number of electronic documents that we store on our phones, tablets and computers may open up a variety of avenues by which probate could become both expensive and contentious.
"While there are arguments on both sides, we take the view that, on balance, electronic documents and audio and audio-visual recordings should fall within the scope of the dispensing power."
Law Commissioner Professor Nick Hopkins said: "Making a will and passing on your possessions after you've died should be straightforward. But the law is unclear, outdated and could even be putting people off altogether.
"Even when it's obvious what someone wanted, if they haven't followed the strict rules, courts can't act on it. And conditions which affect decision-making – like dementia – aren't properly accounted for in the law.
"That's not right and we want an overhaul to bring the law into the modern world. Our provisional proposals will not only clarify things legally, but will also help to give greater effect to people's last wishes."
The consultation closes on November 10.