secure wiping of data

[gsh99]

Hi I am about to sell my S9+ and I know I can do a factory reset but some sites say you should encrypt the data first as its possible to hack into the phone and retrieve personal data - is this correct?

[BandOfBrothers · Accepted solution]

Hi @gsh99 

I can only tell you what I've been doing over many years upon selling my previous phones.

I log out of all sites and security parts of the phone along with Playstore and any banking apps etc and manually delete all cache and history of the browser.

Then I factory reset which takes the phone back to the last successful firmware update and removes personal data.

Will fragments remain ? Possibly but a person would need the right software to go delving around inside the phones core system files and only then get fragments. 

Personally I'm not convinced most of the people that would buy a used phone would do this to explicitly get to fragments of data. 

But instead buy a used phone to get to use a phone they want for cheaper than it costs to buy one sim free or with a network contract.

[gsh99]

Hi and thanks for your response - your suggestion are pretty much what Samsung suggested:  remove Google, Outlook, Pay Pal, Bank Apps & Microsoft account then factory reset and if you are paranoid encypt data first - but there is no need - I think the issue came about when a techie magazine went out and bought 20 old phones then proceeded to hack the life out of them recovering quite a bit of personal data - the average user wouldn't have a clue or would even attempt to do this but maybe there is someone out there who buys up old phone for this purpose - who knows - a little paranoia isn't a bad thing.

"A good deed, however small is never wasted" - anon