The combined terms and conditions of 13 top apps including TikTok, WhatsApp and Zoom would take 17 hours and five minutes to read, a firm has estimated.

The documents contain a joint total of 128,415 words - longer than any one of the first three Harry Potter novels.

The longest was Microsoft Teams at 18,282 words - or two-and-a-half hours of reading time for many people.

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In 2018, a BBC study found that several website policies required university education levels of reading ability.

It is not possible to use the services without agreeing to the terms.

Other long documents discovered by thinkmoney included Candy Crush (14,189 words), Twitter (11,022) and Facebook (8,588). The word count included both terms and conditions and privacy policies.

The shortest on the list was Google Meet with 4,717 words.

Privacy researcher Stephanie Hare said that both the length and language used in such statements made them difficult for adults and children to be able to make informed consent about what they were agreeing to - and the only alternative was to not use the app at all.

"Consent implies choice, but choice is not what's on offer. It is difficult, if not impossible, for most of us to work and live today without using a smartphone, computer and other devices that allow us to transact online," she said.