Phone (Android) Data Security?

[Kijona]

Basically, I've got an HTC EVO 4G (Sprint's branding) that I used for 2.5yrs. I finally decided to upgrade (and thusly lost the 25% discount I had for all that time on my bill). It was/is rooted and loaded with Cyanogen Mod 7 (CM7).

I'd like to sell this phone but I am concerned with all the application data and so-on that's been stored over the years. I used the option from the settings>security menu called "Factory Data Reset" which claimed it would remove all traces of personal data from the phone. I'm not sure if I trust that...opinions? It did completely reset it back to stock CM7 with the first-boot android setup screen.

What are my options as far as making sure my data is gone/safe? I know just formatting doesn't make it "erased" since it only allocates the memory for being "available."

[Malfruen]

You could completely re-flash the phone from top to bottom, such as downloading the original flash file from htcdev.com and overwriting the Cyanogen flash with that. That SHOULD remove all details from the phone.

Save for that, best thing to do would be to start the phone up, plug it into a computer, and do a complete format of the data card via Windows/OSX. Not a quick format, full one. Once it's done that, redo a Factory Data Reset. In saying that, when I used to work as a technician for the man, I had a lady who "accidentally" factory restored her phone. As much as I tried to recover her photos and whatnot from the phone, I could only recover segments of the data (average of about 7-9% of each file), not enough to rebuild the files. Not to say its the same with every phone available, but food for thought.

Only thing someone with rudimentary knowledge of these devices would be able to recover might be photos and music. Texts, contacts, etc are stored in a seperate partition that requires all sorts of rooting and shenanigans to gain access too via PC to recover. Too much work.

[Kijona]

You could completely re-flash the phone from top to bottom, such as downloading the original flash file from htcdev.com and overwriting the Cyanogen flash with that. That SHOULD remove all details from the phone.

Save for that, best thing to do would be to start the phone up, plug it into a computer, and do a complete format of the data card via Windows/OSX. Not a quick format, full one. Once it's done that, redo a Factory Data Reset. In saying that, when I used to work as a technician for the man, I had a lady who "accidentally" factory restored her phone. As much as I tried to recover her photos and whatnot from the phone, I could only recover segments of the data (average of about 7-9% of each file), not enough to rebuild the files. Not to say its the same with every phone available, but food for thought.

Only thing someone with rudimentary knowledge of these devices would be able to recover might be photos and music. Texts, contacts, etc are stored in a seperate partition that requires all sorts of rooting and shenanigans to gain access too via PC to recover. Too much work.

Hey thanks for the tips man. Much appreciated! I'll do that.

[Kiwingenuity]

What Malfruen said - Just a factory reset on its own has left me being able to succesfully recover partial SMS and contact data from most smartphones with the right tools (Android and IoS) since the OS seems to get written to common sectors of flash.

If you use a utility to do a low level format with nice random 1's and 0's before you do a factory data reset - you would struggle to get anything meaningful back off the device.

Simple rule here at work - if its ever had something on it you want no risk of anyone looking at - drill a few nice .44 size holes through it.. all our desktop machines get returned minus the HDD which is run through a chipper..   

[weedahoe]

Agreed on reflash. Put stock ROM back on if you backed it up. If not, try to find it online and flash it. In flashing, it will wipe cache, dalvik, batt stats, ect. Just do not sign back in with your Google acct afterwards

[john]

Agreed on reflash. Put stock ROM back on if you backed it up. If not, try to find it online and flash it. In flashing, it will wipe cache, dalvik, batt stats, ect. Just do not sign back in with your Google acct afterwards

This.

[Malfruen]

http://dl4.htc.com/RomCode/Source_and_Binaries/supersonic-2.6.35-gb-MR.tar.gz

Thats the latest source code available from HTC. It should be branded, as far as normal apps will be on it as if you just bought it from Sprint, but it won't hold any of your data.

[Kijona]

Thanks for all the help guys! Gonna get it going and sell it!

[yamahonkawazuki]

Basically, I've got an HTC EVO 4G (Sprint's branding) that I used for 2.5yrs. I finally decided to upgrade (and thusly lost the 25% discount I had for all that time on my bill). It was/is rooted and loaded with Cyanogen Mod 7 (CM7).

I'd like to sell this phone but I am concerned with all the application data and so-on that's been stored over the years. I used the option from the settings>security menu called "Factory Data Reset" which claimed it would remove all traces of personal data from the phone. I'm not sure if I trust that...opinions? It did completely reset it back to stock CM7 with the first-boot android setup screen.

What are my options as far as making sure my data is gone/safe? I know just formatting doesn't make it "erased" since it only allocates the memory for being "available."

Going to jailbreak a sprint gal s2 or get sprint unlock. ( clean esn sprint should unlock it, then use either another carrier or purchase a mobile wifi terminal. ( less than a hundred, service reasonable i must admit. now you CAN dig deeper once formatted. or hgo in manually and check. this service IS available albeit pricy

[ohgood]

Basically, I've got an HTC EVO 4G (Sprint's branding) that I used for 2.5yrs. I finally decided to upgrade (and thusly lost the 25% discount I had for all that time on my bill). It was/is rooted and loaded with Cyanogen Mod 7 (CM7).

I'd like to sell this phone but I am concerned with all the application data and so-on that's been stored over the years. I used the option from the settings>security menu called "Factory Data Reset" which claimed it would remove all traces of personal data from the phone. I'm not sure if I trust that...opinions? It did completely reset it back to stock CM7 with the first-boot android setup screen.

What are my options as far as making sure my data is gone/safe? I know just formatting doesn't make it "erased" since it only allocates the memory for being "available."

just flash cm again, and keep your microsd card. no worries.

the only way to prevent reading blocks is to destroy the phone, overwriting it multiple times is not fail proof.

[yamahonkawazuki]

Basically, I've got an HTC EVO 4G (Sprint's branding) that I used for 2.5yrs. I finally decided to upgrade (and thusly lost the 25% discount I had for all that time on my bill). It was/is rooted and loaded with Cyanogen Mod 7 (CM7).

I'd like to sell this phone but I am concerned with all the application data and so-on that's been stored over the years. I used the option from the settings>security menu called "Factory Data Reset" which claimed it would remove all traces of personal data from the phone. I'm not sure if I trust that...opinions? It did completely reset it back to stock CM7 with the first-boot android setup screen.

What are my options as far as making sure my data is gone/safe? I know just formatting doesn't make it "erased" since it only allocates the memory for being "available."

just flash cm again, and keep your microsd card. no worries.

the only way to prevent reading blocks is to destroy the phone, overwriting it multiple times is not fail proof.

only thing failproof is fire or destruction lol. agreed there