Bitcoin Forum

Hi,

I am looking to create my own hardware wallet where I can store a good bunch of Bitcoins (100+ BTC) and also have the ability to transfer them fast qith QR codes. I have trezor which is something like this but I thought that it could be a good idea to do something with this spare S5 to create something secure.

How would you do this? I would need it to connect to the internet for transactions but how can I prevent being hacked since its android? Will an Iphone work better?

I know mycellium could do something like this, please be detailed on what is the best setup.

I like paper wallets but they become hard to spend sometimes if needed.

Thanks

i cant help you with that but just an adive:

splitting your funds would be more secure than putting 100BTC on your phone.

Yes, it wouldn't act as a phone since I have my phone it would be a hardware wallet which will be limited to BTC only I wouldn't install nothing more. I have my regular phone for daily use.

Thanks

why not use the trezor?

Phones aren't really great to use as hardware wallets. I would suggest using tezor, or alternatively you could send the 100 mBTC to a paper wallet for cold storage.

I will only recommend that only if the S5 runs a full Linux distro natively. Android is a very dynamic OS, an update in his internal .apks or the OS itself can ruin everything your wallet does (permission things, connection capabilities, etc)
Another thing to considerate is a full backup routine, maybe every week or something like that. (and I don't know if that will break the "full autonomous hardware wallet" principles)

You should wait at least until Samsung releases patches for Stagefright bug. That should happen quite soon, please see

https://www.theverge.com/2015/8/5/9099627/google-stagefright-android-vulnerability-protect-patch
http://www.zdnet.com/article/after-stagefright-samsung-and-lg-join-google-with-monthly-android-patches/

I would definitely agree using a paper wallet.... More secure plus much more smaller so you can easily hide it away (and forget about it xD)

If you are connecting to Internet, it may not be good to store huge amount of Bitcoins in a phone. Actually, IMHO, huge amounts of Bitcoins should be stored in cold storage even if you are a computer geek.

You must wipe your phone completely and start fresh. It's better not to install any app other than the wallet you are using.

not a good idea i think.
what if someone stole you phone?

What if someone stole your paper wallet? What if someone stole your hardware wallet(Trezor, Case, HW1 etc...)?

There will be a risk.You can devide your risks but you can not decrease the total risk.It can be stolen, formatted or lost.

I do not recommend my way but I will just tell what I do.I have hired a safe (deposit box) at a local bank.I have my paper BTC wallets stored there.

Do I have a risk?Yes.If the bank is robbed or a fire takes place my investment is gone.

So far, all of the folks saying it's not a good idea haven't really said why it would or wouldn't work.

If I were going to do this, I would:

* Install Cyanogenmod and a propery recovery
* Go ahead and remove the radio blobs so the phone has no way to connect to cell phone networks

At this point, you're sure that you have a non compromised android.  You could then use Andreas Schildbach's bitcoin wallet for andoird as it's an open-source wallet you can check for issues.

Finally, it goes without saying that you'd want to make a backup of the entire device (but especially the private keys).

Okay, so, if this is not a good idea, lets hear why, not just "not a good idea".

I think it would be smarter to split your funds between paper wallets and your Trezor device. I guess nothing keeps you from keeping a small amount on your S5 though.

Surely nothing keeps him from keeping any amount on an S5.  But I thought that this thread would be about the technical details of the effort (this is the technical discussion board).  Seems like 90% of the posters in this thread just can't help saying "I don't like your idea".  But come'on, people, surely someone has a technical opinion if you want to hang out in this board.