In short, in some circumstances replying with a thumbs-up emoji to a photograph of a contract can be as legally binding as signing the contract.
"In a summary judgement that contained 24 instances of the emoji, Judge T J Keene resolved the issue by ruling that a thumbs-up emoji is enough to accept contractual terms."
"In a summary judgement that contained 24 instances of the emoji, Judge T J Keene resolved the issue by ruling that a thumbs-up emoji is enough to accept contractual terms."