Bitcoin Forum

I want to use an old Android Phone as wallet insted of my actual blockchain.info wallet
I want to reset it as new and to keep it only as a bitcoin wallet (only bitcoin) .
I will open it rare becouse i will check my balance in blockchain.info and i use it only for storage .
My question is , what software to use becouse i'm affraid of non-open source wallet like coinomi and i want a good backup becouse is a phone and can die.
thank you .

If you want to secure your crypto use hardware wallet instead of your mobile phone. I am really skeptical leaving my crypto in any online wallet esepcially in my phone. It is risky since I use my phone everyday and it might get lost (different in your case since you will not use your phone as you said.) But, if you really carw about your security better use hardware wallet.

But in his case we suppose he won't use it daily, it will be only a smartphone used for cold storage.

@Nofearboy
There are several like the ones mentioned here (https://bitcoin.org/en/wallets/mobile/android/) , it depends on what you're looking for. Also, there is a dedicated section for Android wallet (Bitcoin Wallet for Android (https://bitcointalk.org/index.php?board=100.0)) maybe there are topics that will help you to decide. As long you don't use a hosted wallet you're fine.

Suggestion: use the phone for small amounts, and use paper wallets for long term storage.
If you do this, take the necessary precautions such as creating the paper wallets offline.

It doesn't matter whether it's small or big. I think mobile devices are very risky tools. If the goal is to keep the cryptocurrencies safe only if you have, there are 2 best methods.

1) If the amount of cryptocurrencies you want to keep safe is a bit much, then the hardware wallet.

2) "paper wallet" for small amounts of investments. (In my opinion, this is the most reliable method. Unless you lose the private key!)

But I think such wallet have security seeds that only you have. Apart from the possibility of hacking, only you can access the wallet even if lose the phone. You can restore you wallet if you saved your seed.

Not recommended to use old phones as your cold wallet because the android version is not updated and I'm sure old android version won't support new versions of any wallet you want in the future.

If you actually want a wallet offline there are some alternative like Electrum Tails in USB or Airgap wallet where your one wallet is in another Android device that includes private keys and seed and another Android device with airgap wallet(offline) as a watch only wallet.

I'm thinking about the same idea but making the old android phone as an offline airgapped wallet
I would have another phone with online connection with watch-only mode to pair with
so raw transaction will be passed back and forth via QR code,
offline phone signs the transaction and online phone broadcasts it to the network
is this possible with mobile wallet? electrum apps? or other wallet recommendations?

Using an old Android phone is a bad choice, the old internal and external memory of Android is very small and limited.  we can't use that. 
you better choose a new android that has more memory.  some wallets that can be used are blockchain, coinbase, arax, javvy.  and others. 
or you can use samourai mobile.  mobile phones that can send crypto without internet.  and only use SMS.

If that will be the sole purpose, I'm not going to use that for bigger amounts.

And instead of choosing blockchain.com wallet app, I'll choose a better wallet although I had no issues with them but it's just me that has that kind of feeling that there's a better wallet app and that's like electrum app. Since you will not open it for a long time, just purchase a hardware wallet.

Why not use a hardware wallet instead of your old phone?
It is much more safer compare to your phone and it is hard to trust any mobile wallet this days.
But if you still want to continue then I think I only trust MEW just download your JSON file,
I use a flahsdrive to keep it safe but you could also use your phone .

Ok ,you convinced me , thank you .
I will buy a Ledger.

if you are going to choose between a web wallet (blockchain.com) and an old phone then obviously the old phone wins but it is not really a good idea to use that as a bitcoin wallet in my opinion, phone wallets are less used and have so few features and sometimes they are not as secure as the desktop versions.

as for Ledger wallet, it is a good wallet if you are ok with paying that much for a bitcoin wallet! and also if you have large funds which you want to store and also regularly access. otherwise I would go with traditional cold storage options such as a paper wallet if it is large and for long term storage.
you should also remember that every single method of storage will have both advantages and disadvantages. there is no one perfect solution. you must study each and even try each method and see which one is best for your individual situation.

There is no question here, hardware wallet remains to be the safest alternative you can use except of course if you have the propensity to experiment just be careful if that is the case because one you lost your coin then it can take a lot of effort, time and headaches to restore them back. Getting the Ledger then can be your best decision. Good luck with your cryptocurrency experience...

Huh?

The internal memory is large enough to store a single application and a few kilo bytes of data...
And if you can insert an SD card, those mobiles usually support more than a few GB.. Way more than one would need.




You can't send crypto without internet. You need an internet connection.
Whether it has to be on the device itself (not recommended) or on another device, is another question..

Also.. use SMS for what ? SMS is not the safest way to communicate..

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@OP:
Since your question has been answered and you have decided what to do, consider closing this thread to avoid future spam (bottom left corner -> lock topic).



Edit:
Exactly this is the kind of spam i am talking about:

Sure enough, the more years the application development gets higher and requires a device that can support the application, surely one day if you open an application from your old cellphone it won't work and this can be a disaster for you.

You want to secure all your cryptocurrency instead of using a cellphone. You have to use a device that is really good and reliable. I think keeping a bitcoin with a cellphone is not good because if it happens your cellphone is damaged and you lose all other bitcoin cryptocurrency so that is not an idea good for me, you can use software that is trusted by all bitcoin users

Well, if you are a really expert in doing that it is good for you just to do it and not buy hardware wallet because some of them are expensive but at least legit. Just remember that you should always keep in your mind that don't forget or lose that old android phone because all your money is on it. But, if you are not good keeper then don't use that old android as a wallet for bitcoin.

Using SMS to send a signed raw transaction... For that you don't need a safe transmission.

The raw transaction will take up more than the 160 characters a single SMS will allow, so you'll have to send a multi-part SMS or MMS.

In that case, just use a network connected phone to send your transaction using either Bitcon for Android or Electrum for Android. They both work fine for this purpose.

If that phone has been factory reset and has no other apps, it's decently safe. However, as others have said, the moment you intend to store thousands of dollars worth on such devices, a hardware wallet may make more sense.

A few people I know store up to 50 BTC on their mobile phone wallets. Depends on your risk tolerance, can you afford to lose your phone or have no backup or it gets stolen, or someone with a hacked wifi access point listens to everything .... public open wifi is not safe. Your own personal mobile data maybe safer, at least you're paying for it.

Yes but many people can't use their "data connection" on their phone when they are abroad and in many places there isn't 3G or 4G network, so sending your signed raw transaction on the GSM network by SMS can be a helpful solution.

Old android mobiles are rather bad choice, old androids do not receive updates, it makes them prone to vulnerabilities.

I don't recommend old androids to store your crypto.

South Korea is an advanced country in the application of blockchain technologies. Support for bitcoin and more than 30 currencies in the internal crypto wallet of the phone is progressive. I heard that they are also working on a more secure user identification system. With this addition, they will not have equal competitors

I saw the Wings project this smartphones also with a crypto wallet and built-in mining function. But mainly targets ethereum. Also cool design. Samsung has the same quality guarantee. Especially if Apple does not release its answer to an eastern competitor. And this event can be delayed, because in Korea cryptocurrencies laws are unlike the United States