Used Android phone: How can I make sure there is no spyware installed?

[androidisforporn]

I am new to Android and I am thinking about buying a used Android phone, but I am worried there may be some spyware installed by the previous owner.

I am not worried about James Bond style hardware bugs, only what you can install using custom ROMs and stuff like that. Basic hacking skills any 12 year old can learn searching the web and wanting to have some mischievous fun.

What should be the first thing I do if I buy such a phone and want to "scrub it clean" before I start storing my passwords and personal photos on it?

Is there a factory reset that is guaranteed to work even if a hacked ROM has been installed? (Not talking about custom ROMs where you see there is a different interface, but a custom ROM that looks just like the original only with some spyware included inside.)

Maybe I am paranoid but I would rather be that than being a fool that looses all my data to a school kid that posts it all over the web. Of course I could buy a new phone but my budget is a bit tight and I would not like to wait another 6 months before I get a proper phone.

Please help

 

[sonofaresiii]

You can certainly do a factory reset, it's very easy to do, once you get your phone do a search on here for how to do it (check the sub-forum for your particular phone, I'm not sure if it's the same on all androids).

That'll clean everything off your phone and put you back at an out-of-the-box experience.

Welcome to Android, you'll love it! And check back on these forums on how to get the most out of your phone-- they're great right out of the box, but there's so much more you can do with them beyond that.

 

[androidisforporn]

You can certainly do a factory reset, it's very easy to do, once you get your phone do a search on here for how to do it (check the sub-forum for your particular phone, I'm not sure if it's the same on all androids).

That'll clean everything off your phone and put you back at an out-of-the-box experience.

Thank you for answering!

I was thinking that if I install a new ROM I would replace the factory settings but that is not the case? Can I always get back to factory reset version no matter what custom ROM has been installed before? If so can I experiment with any number of custom ROMs and always be able to return to the clean and safe factory reset version?

 

[sonofaresiii]

These are really questions that are kind of phone-specific, so you may be better off picking a specific phone and asking in the sub-forum... but in my experience with the DX:

Yes, you can always return to stock settings no matter what you do, but some ways may be a little more intense than others (though nothing too hard).

Most ROMs will require you to do a factory reset before you flash the ROM, so you will in effect always be at factory settings before you install something new.

Again, I can only speak for the Droid X, and there may be some phones that operate slightly differently... but I'm pretty sure that anytime you flash a ROM, you'll be able to also flash back to stock settings-- in effect, you can think of stock settings as just the company-made ROM. I *think* so long as you have root you can flash whatever you want on any phone, and as far as I'm aware all phones can be rooted, but that could change with updates (though probably won't).

 

[androidisforporn]

Thank you again sonofaresiii

I did not know there could be differences in this between the different models. Coming from the outside I now understand more the problem of Android fragmentation, and why normal simple people flock to the iphone

I guess I should find a specific phone I want to buy and then ask in the appropriate forum for that phone for the details.

 

[snapper.fishes]

You can certainly do a factory reset, it's very easy to do, once you get your phone do a search on here for how to do it (check the sub-forum for your particular phone, I'm not sure if it's the same on all androids).

That'll clean everything off your phone and put you back at an out-of-the-box experience.

Welcome to Android, you'll love it! And check back on these forums on how to get the most out of your phone-- they're great right out of the box, but there's so much more you can do with them beyond that.

Incorrect. A factory reset will not achieve anything at all if the ROM was modified. Factory reset does not touch the /system partition, which is where any spyware will reside.

To be 100% sure, you will need to learn how to flash roms yourself, and flash a stock rom on the phone again.

 

[androidisforporn]

Incorrect. A factory reset will not achieve anything at all if the ROM was modified. Factory reset does not touch the /system partition, which is where any spyware will reside.

To be 100% sure, you will need to learn how to flash roms yourself, and flash a stock rom on the phone again.

Thanks a lot for clearing that up!

The factory reset was too good to be true then

So basically if I buy a phone from someone (say my cousin) and suspect someone (her 12 year hacker son) might have tampered with it, my first thing to do if I want to be secure should be to flash the ROM? Is that correct?

Could I then be absolutely sure there is no possible spyware in the system installed by the previous owner(s)?

Are officially released ROM images available for most phone models? Only from certain manufacturers? Or would I need to get it from my network provider (who certainly does not offer any in my country)?

If no official ROM is provided, would my best (perhaps only) option be to install CyanogenMod or another hopefully reputable customized ROM?

 

[sonofaresiii]

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