If you're currently setup with an Apple ID, you'll need to take a bit more care when deleting your browser history. It has been found that iCloud will store your history indefinitely – which raises serious privacy and security questions for apple.
Discovery was an accident
A renowned Russian hacker made the discovery; Vladimir Katalov, CEO of Elcomsoft. Vladmir stated to Forbes that he had originally uncovered the issue by accident when testing his own software on his iPhone. Vladmir discovered a directory titled "tombstone", in which deleted web visits were stored, ostensibly for syncing across devices.
Apple syncs data between your Apple devices using iCloud, a remote server that syncs data between clients. Servers normally do need a log of deleted data as well to ensure that syncing happens properly, but this data is usually very well hidden.
Importance of privacy and security
Jay Stanley, senior policy analyst at the American Civil Liberties Union (ACLU), said companies had to be very careful to follow best practise and delete users' data when requested. "Overall, assuming this was a mistake, it's a reminder that storing and retention of data is the default as a technical matter," Stanley said.
"Browsing history is a very sensitive set of data. It reveals people’s interests, concerns, worries and in many cases their every fleeting thought, as well as health information”
"It's vital that people are able to trust that they can be in control of that kind of information. It's one reason we advise using search tools that don’t store your history."
The best way to avoid getting caught up in this whole hassle is to simply disable iCloud syncing features, particularly on Safari. Apple has a good guide about how to turn iCloud features on and off here.
For more information, please visit http://www.forbes.com/sites/thomasbrewster/2017/02/09/apple-safari-web-history-deleted-stored-icloud/#182ad1312439