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Other => Beginners & Help => Topic started by: Charles-Tim on April 03, 2020, 11:27:31 AM



Title: Using mobile phone as a full mobile wallet
Post by: Charles-Tim on April 03, 2020, 11:27:31 AM
This could be so hilarious but I just need you to contribute.

If someone has two mobile phones, deciding to use one as a mobile wallet. To me, this is a good idea as one of the phones can be useless. And having in mind to use it as wallet and putting these in consideration.

Having back up of his private keys or seed phrase.
Not using it to go online but online while making transactions
Still install anti malware against malware

So, he use the phone only as wallet and for crypto transactions. So, what do you think. Is this a good idea?


Title: Re: Using mobile phone as a full mobile wallet
Post by: nc50lc on April 03, 2020, 11:34:01 AM
2 Mobile phones? Then it's better to use the other one as a cold-storage for signing transactions,
and use the main online phone as the paired watch-only wallet for monitoring the balance and creating transactions.
It's a lot safer than just using one of the phones as a wallet.


Title: Re: Using mobile phone as a full mobile wallet
Post by: Charles-Tim on April 03, 2020, 11:43:23 AM
2 Mobile phones? Then it's better to use the other one as a cold-storage for signing transactions,
and use the main online phone as the paired watch-only wallet for monitoring the balance and creating transactions.
It's a lot safer than just using one of the phones as a wallet.

I am still new and this sounds new to me. How can this be done?
Please, do you have any article for this?


Title: Re: Using mobile phone as a full mobile wallet
Post by: NeuroticFish on April 03, 2020, 11:49:33 AM
Not using it to go online but online while making transactions

This is still unsafe. As long as it goes online even for a minute, hacks can happen.

To be more clear, did you mean to use it as a multisig wallet?

He said it right, he meant cold storage.
One phone stays offline ever and it's used only to sign transactions. The normal phone has watch only wallet, can make transactions, can broadcast transactions, can see the status of the funds, but it needs the "cold" phone for signing. Of course, the information transfer will not happen through internet, since the "cold" phone will always stay offline.

Edit: things to read (they are for computer/laptop, but you will get an idea)
https://bitcointalk.org/index.php?topic=3171247.0
https://electrum.readthedocs.io/en/latest/coldstorage.html


Title: Re: Using mobile phone as a full mobile wallet
Post by: nc50lc on April 03, 2020, 11:50:49 AM
To be more clear, did you mean to use it as a multisig wallet?
Uh, nope.
What I described is a cold-storage set-up which is a lot secure than directly using a mobile as a wallet.

You can use two Electrum mobile to do that and phones with working camera (Only download Electrum from: https://electrum.org/#download (https://electrum.org/#download)).
One offline phone containing the seed and another one with just the master public key that can't be hacked.

Please, do you have any article for this?
I'll edit this post / reply with the steps since I haven't found a tutorial for electrum mobile in the internet.


Title: Re: Using mobile phone as a full mobile wallet
Post by: Twinkledoe on April 03, 2020, 11:54:08 AM
In my opinion, that's fine with me as long as you are not storing your other coins. If you will just use it for payment transactions and not really storage of your important ones, just for convenient purposes of your short term transactions. Because at some point, you might lose it for no reason. Just think of the worst possible scenario so you know what contingencies you will do if it really does happen.


Title: Re: Using mobile phone as a full mobile wallet
Post by: nc50lc on April 03, 2020, 12:18:18 PM
Okay, here's the procedure to create a cold-storage mobile Electrum wallet:
  • 1. Install Electrum on both devices, and create a standard wallet on the "cold storage" device, that will be your main wallet that contains all the keys and shouldn't be connected to the internet even once (a newly formatted device/new device is better).
    Make sure that the seed was saved in a physical backup like a piece of paper.
  • 2. Click the wallet's name on top of the screen and click "Master Public key" twice to open the QR code.
  • 3. On the online phone, create a new wallet using the option "Standard Wallet->Use a master key", then click the camera icon to scan the cold-storage wallet's QR code.
    This will create a watch-only wallet version of your cold-storage wallet.
  • 4. Confirm if the address in the receive tab is the same.

Now to use those wallets:
  • You just have to create a transaction using the online watch-only wallet using the send tab.
  • Fill out the recipient, amount, etc. then, click pay (select if you want to opt-in RBF, yes) and click the QR code icon below.
  • In the cold-storage wallet, go to send tab and click the camera icon on the right side and scan the other device's QR code.
  • The transaction will be imported to the cold-storage wallet, now click option->sign (enter your pin) and it will be marked as "signed" above.
  • Click the QR code icon, then scan this using your online watch-only wallet and the signed transaction will be imported and now you can use options->broadcast button to send it to the network.

If you're not familiar with Electrum's defaut bitcoin denomination, you can change it from mBTC to BTC in the settings->denomination.


Title: Re: Using mobile phone as a full mobile wallet
Post by: CucakRowo on April 03, 2020, 12:21:15 PM
Using mobile phone (one of two) as a full mobile wallet. Why not?
As long :
- The phone has no social media installed or any other programs (like games, etc). Phone is dedicated solely for crypto.
- The phone active and online only for transactions.
- There are no seeds, private key stored in the phone (please avoid this). Save it in other place.



Title: Re: Using mobile phone as a full mobile wallet
Post by: Charles-Tim on April 03, 2020, 12:22:21 PM
This is so informative, thanks so much. So far you talk about the phone camera, it means I can make use of QR code to easy complete the transactions by using the cold mobile device for signing. It is a lot better than using USB stick.


Title: Re: Using mobile phone as a full mobile wallet
Post by: hatshepsut93 on April 03, 2020, 01:08:50 PM
This setup might be viable if you can't afford a real hardware wallet and you have a spare phone that can be turned into a cold storage, but if you want to buy a new phone for that, you'd better just buy a hardware wallet instead. This setup is less secure than a hardware wallet, your phone might have some spyware installed by the vendor, especially if it's a cheap phone, and it can be trying to connect to networks even without your permission.


Title: Re: Using mobile phone as a full mobile wallet
Post by: RapTarX on April 03, 2020, 01:13:42 PM
When a wallet gets connected with online, it's not safe anymore regardless of what step you take or whatever. I don't know if it's possible to create multisig wallet from mobile; that would be the best idea keep fund safe.


Title: Re: Using mobile phone as a full mobile wallet
Post by: mk4 on April 03, 2020, 01:23:52 PM
Theoretically you can do it. It's just going to be tough and it's going to take a good amount of research and effort to reach higher security. If you really really want a secure device, it's not going to be as easy as uninstalling all apps and leaving just one wallet app. If you really want security, you'd probably have to encrypt the phone's storage, and use a better mobile OS, probably like Graphene OS or an OS that doesn't have wifi and data drivers if you really want a cold storage.

But to be honest, spare all the headaches and just purchase a hardware wallet lol. Unless you enjoy having to tinker with devices, then feel free to go with that setup.


Title: Re: Using mobile phone as a full mobile wallet
Post by: Lucius on April 03, 2020, 01:32:39 PM
Mobile wallet as "main or full storage" it's never a good idea, although in the absence of any other choice there are several things to keep in mind. The first in my opinion is definitely the choice of a smartphone, because if you want to have relatively secure hot wallet you need a secure device, and by that I mean the newest OS that will receive security patches on a regular basis. Then such a phone should be adequately protected (in the same way as a desktop computer) and only then can we install a proven mobile crypto wallet.

Of course, cold storage is a much safer choice, and if you have an older smartphone why not try to secure your funds in a completely free way.


Title: Re: Using mobile phone as a full mobile wallet
Post by: Sonu_titu on April 03, 2020, 02:04:40 PM
This could be so hilarious but I just need you to contribute.

If someone has two mobile phones, deciding to use one as a mobile wallet. To me, this is a good idea as one of the phones can be useless. And having in mind to use it as wallet and putting these in consideration.

Having back up of his private keys or seed phrase.
Not using it to go online but online while making transactions
Still install anti malware against malware

So, he use the phone only as wallet and for crypto transactions. So, what do you think. Is this a good idea?


Instead of buying a extra phone you can buy a hardware wallet and store the seed by writing down on a paper. Hardware wallets are far more better than mobile wallet.


Title: Re: Using mobile phone as a full mobile wallet
Post by: taufik123 on April 03, 2020, 03:09:43 PM
Better advice than using 2 cellphones as a mobile wallet and making transactions.
Instead of buying a extra phone you can buy a hardware wallet and store the seed by writing down on a paper. Hardware wallets are far more better than mobile wallet.

Hardware wallet will certainly be safer compared to mobile wallet, because the hardware wallet has better security and can also be synchronized with your cellphone or computer, depending on the features provided by the hardware wallet used.

The use of a mobile wallet has many risks if you are not aware of its use, one of which is malware that will attack the security of your cellphone. To overcome this, periodic scanning should be done to ensure there are no viruses or malicious applications installed on your cell phone.

But still the use of hardware wallet is better and safer compared to using 2 cellphones as the method you use.


Title: Re: Using mobile phone as a full mobile wallet
Post by: madnessteat on April 03, 2020, 04:30:56 PM
~snip~

Of course it's possible to use a smartphone for cold storage, but I don't see the point in reinventing the bike.

I fully support mk4 that you better buy a hardware wallet (Ladger, Trazor) or use Raspberry Pi 4 and Electrum for cold storage of bitcoin.


Title: Re: Using mobile phone as a full mobile wallet
Post by: Shimmiry on April 03, 2020, 05:02:25 PM
This could be so hilarious but I just need you to contribute.

If someone has two mobile phones, deciding to use one as a mobile wallet. To me, this is a good idea as one of the phones can be useless. And having in mind to use it as wallet and putting these in consideration.

Having back up of his private keys or seed phrase.
Not using it to go online but online while making transactions
Still install anti malware against malware

So, he use the phone only as wallet and for crypto transactions. So, what do you think. Is this a good idea?


I think it's not a good idea. Why? Almost every smartphones are vulnerable to threats even you install many anti-virus and anti-malware in it. And having your money and private keys stored in just a single device makes it much riskier. If you would only use it for the private key and seed phrase storage, what if you lost it or you accidentally broke it? Better to have backups in a lot of platforms. And, why not use hardware wallets instead?


Title: Re: Using mobile phone as a full mobile wallet
Post by: libert19 on April 04, 2020, 03:37:34 AM
Kinda off topic but why not buy a hardware wallet and use it with your phone with otg cable? That will be much more secure imo. Will be more convenient than having 2 phones as well.


Title: Re: Using mobile phone as a full mobile wallet
Post by: boyptc on April 04, 2020, 04:37:44 AM
Someone has shared the same idea before and it's also with the use of an extra laptop. But rather than using a phone as a cold storage better to use the hardware wallets that we use like ledger.

Sell the phone that you won't use anymore and use the money to purchase a hardware wallet.


Title: Re: Using mobile phone as a full mobile wallet
Post by: bakasabo on April 04, 2020, 07:46:22 AM
Chances of your second phone with mobile wallet app being stolen, lost, broken, becomes suddenly a brick after a new firmware update is higher than simply holding funds on a ledger/trezor like hardware wallet.

Imagine your are keeping your phone at home and suddenly someone brakes in. First thing he will steal will be gadgets like phones, laptops - something that will be easy to sell in pawnshop. But who would take cheap usb flash drive, sorry crypto hardware wallet?

Plus this hardware wallets have built in security, and your mobile has? Pin code ? Home screen protection code ? :D


Title: Re: Using mobile phone as a full mobile wallet
Post by: ampere on April 04, 2020, 09:15:28 AM
This could be so hilarious but I just need you to contribute.

If someone has two mobile phones, deciding to use one as a mobile wallet. To me, this is a good idea as one of the phones can be useless. And having in mind to use it as wallet and putting these in consideration.

Having back up of his private keys or seed phrase.
Not using it to go online but online while making transactions
Still install anti malware against malware

So, he use the phone only as wallet and for crypto transactions. So, what do you think. Is this a good idea?


I also use this type of strategy, one phone contains all my crypto currency wallets, while i have my seeds saved privately.

The only thing i do not agree with is anti malware, either for your mobile phone, or your laptop, you do not need anything called anti malware.
For your phone and pc, all you have to do is activate the windows malware defender thats inbuilt with the devices, then you are safe.


Title: Re: Using mobile phone as a full mobile wallet
Post by: Lucius on April 04, 2020, 10:29:47 AM
Chances of your second phone with mobile wallet app being stolen, lost, broken, becomes suddenly a brick after a new firmware update is higher than simply holding funds on a ledger/trezor like hardware wallet.

There is always a chance that something bad happens, but there is something called a backup that works on the same principle for any type of wallet. When something is stolen or broken, we use backup to recover lost information. The only difference with what is stolen is how good the protection of a particular device is, or rather to say how long it will take a thief to hack protection and steal assets.

Plus this hardware wallets have built in security, and your mobile has? Pin code ? Home screen protection code ? :D

I wouldn't agree that the thing is so simple, it actually depends on the device itself - whether it's a smartphone or a hardware wallet. Security in for example Trezor HW is somehow compromised because there is an unrecoverable exploit that allows a thief to retrieve a seed in a very simple and fast way if the user has not set a passphrase.

Looking at the average smartphone, these newer ones have a fingerprint reader, PIN and face locking, but I think every mobile wallet is had PIN lock (at least Electrum is have), and you can encrypt your data as additional protection. Which would be easier to hack in a specific case, Trezor HW or smartphone locked with PIN/fingerprint + extra pin for crypto wallet+data encryption?



The only thing i do not agree with is anti malware, either for your mobile phone, or your laptop, you do not need anything called anti malware.
For your phone and pc, all you have to do is activate the windows malware defender thats inbuilt with the devices, then you are safe.

It is never wise to underestimate the enemy, in this case malware, spyware or adware - and I personally have great confidence in Malwarebytes Premuim protection who has been serving me very well for years. What is a problem for most of those who do not want to use commercial av/antimalware programs is their cost and the old myth that they use too much resources and slow down their computers. But on devices that have sufficient RAM, this impact is almost negligible.


Title: Re: Using mobile phone as a full mobile wallet
Post by: Teinkle on April 06, 2020, 10:28:25 AM
I don't stay home coz i work mobile so it is easiest for me to have my ohone as my full e wallet. I store all my coins in different wallets over my mobile phone.


Title: Re: Using mobile phone as a full mobile wallet
Post by: Saint-loup on May 20, 2020, 09:22:40 AM
Okay, here's the procedure to create a cold-storage mobile Electrum wallet:
  • 1. Install Electrum on both devices, and create a standard wallet on the "cold storage" device, that will be your main wallet that contains all the keys and shouldn't be connected to the internet even once (a newly formatted device/new device is better).
In fact it's better to remove the sim card or to only use an out of order one if your device can't work without one.
Because a malware could try to send your seed by SMS or by a phone call if it can't connect to internet.


Title: Re: Using mobile phone as a full mobile wallet
Post by: NavI_027 on May 20, 2020, 10:16:01 AM
So, what do you think. Is this a good idea?
Yeah of course it was a good idea because I've done it. I actually had two smartphones before. One for texting, music and accessing this forum — the phone I normally used outside — and the other one is for my wallet digital wallet as well as the storage for my important files and notes. Unfortunately, the latter one broke due to excessive gaming ;D. Nevertheless, I can say that it was a good way of securing your account against theft or getting misplaced. But this is only practical if you have two phones already.


Title: Re: Using mobile phone as a full mobile wallet
Post by: jademaxsuy on May 22, 2020, 09:02:58 AM
So, what do you think. Is this a good idea?
Yeah of course it was a good idea because I've done it. I actually had two smartphones before. One for texting, music and accessing this forum — the phone I normally used outside — and the other one is for my wallet digital wallet as well as the storage for my important files and notes. Unfortunately, the latter one broke due to excessive gaming ;D. Nevertheless, I can say that it was a good way of securing your account against theft or getting misplaced. But this is only practical if you have two phones already.
I haven't tried it yet because I don't have another mobile phone but it is indeed a good idea to use other phone for wallet. Base on previous post about someone (theif) breaking in to your house and steal yoir gadgets left at home is to create a hiding place for your phone to hide and It is possible to do so just make sure it is hard to notice that there is a hidden compartment.


Title: Re: Using mobile phone as a full mobile wallet
Post by: KrisAlex18 on May 22, 2020, 12:27:30 PM
I don't think that this would be a great idea because there also a possibility that the second phone might be broken and stolen by other people. Having a phone and using only for online transactions is not 100% sure as well because all things happen online can be hack or attacks by hackers. The offline wallet will still be the safest wallet for me it is the safest wallet compared to other types of wallets. It is not accessible by hackers, the only thing Tuscan be the reason for losing your money when using it is when it gets broken.
Okay, here's the procedure to create a cold-storage mobile Electrum wallet:
  • 1. Install Electrum on both devices, and create a standard wallet on the "cold storage" device, that will be your main wallet that contains all the keys and shouldn't be connected to the internet even once (a newly formatted device/new device is better).
    Make sure that the seed was saved in a physical backup like a piece of paper.
  • 2. Click the wallet's name on top of the screen and click "Master Public key" twice to open the QR code.
  • 3. On the online phone, create a new wallet using the option "Standard Wallet->Use a master key", then click the camera icon to scan the cold-storage wallet's QR code.
    This will create a watch-only wallet version of your cold-storage wallet.
  • 4. Confirm if the address in the receive tab is the same.

Now to use those wallets:
  • You just have to create a transaction using the online watch-only wallet using the send tab.
  • Fill out the recipient, amount, etc. then, click pay (select if you want to opt-in RBF, yes) and click the QR code icon below.
  • In the cold-storage wallet, go to send tab and click the camera icon on the right side and scan the other device's QR code.
  • The transaction will be imported to the cold-storage wallet, now click option->sign (enter your pin) and it will be marked as "signed" above.
  • Click the QR code icon, then scan this using your online watch-only wallet and the signed transaction will be imported and now you can use options->broadcast button to send it to the network.

If you're not familiar with Electrum's defaut bitcoin denomination, you can change it from mBTC to BTC in the settings->denomination.
Such an informative reply mate, thanks for sharing, I will try this one someday.


Title: Re: Using mobile phone as a full mobile wallet
Post by: JoMarrah Iarim Dan on May 22, 2020, 03:15:53 PM
2 Mobile phones? Then it's better to use the other one as a cold-storage for signing transactions,
and use the main online phone as the paired watch-only wallet for monitoring the balance and creating transactions.
It's a lot safer than just using one of the phones as a wallet.
I agree to this. When we are making signing transactions it is kinda risky sometimes. Our wallet can be easily detected and hacked. But since the other is only used by monitoring then yes it is safe. For me it is also OK to put my wallet on my mobile phone coz unlike desktop or laptop or pc, I can bring it everywhere. But of course I am very carefulcoz I might misplaced ot lose my phone which happened to be my everything.


Title: Re: Using mobile phone as a full mobile wallet
Post by: AakZaki on May 22, 2020, 07:32:43 PM
I agree to this. When we are making signing transactions it is kinda risky sometimes. Our wallet can be easily detected and hacked. But since the other is only used by monitoring then yes it is safe. For me it is also OK to put my wallet on my mobile phone coz unlike desktop or laptop or pc, I can bring it everywhere. But of course I am very carefulcoz I might misplaced ot lose my phone which happened to be my everything.
Using a mobile wallet is indeed more efficient, practical and portable. The risk of a mobile wallet certainly depends on the security of the smartphone and also depends on the user. Do not install third-party applications that you do not trust. To anticipate when the phone is lost, use screen lock security and make sure your phone is still connected to the internet to keep track of it when your phone is lost.


Title: Re: Using mobile phone as a full mobile wallet
Post by: raymondavid1 on May 23, 2020, 08:45:42 AM
Well, this sounds like a good idea if you can afford two phones. But there are people here that might no be able to afford two phones.
- My advice for you is to try as much as possible not to save your private key on your e-mail.
- write down your private key on a piece of paper. Don't write it down letter for letter, try and add some few extra letters so as to avoid someone using it in your absence...
- ALWAYS CLEAR YOUR CACHE


Title: Re: Using mobile phone as a full mobile wallet
Post by: Subbir on May 28, 2020, 02:25:41 PM
So, what do you think. Is this a good idea?
Yeah of course it was a good idea because I've done it. I actually had two smartphones before. One for texting, music and accessing this forum — the phone I normally used outside — and the other one is for my wallet digital wallet as well as the storage for my important files and notes. Unfortunately, the latter one broke due to excessive gaming ;D. Nevertheless, I can say that it was a good way of securing your account against theft or getting misplaced. But this is only practical if you have two phones already.
I haven't tried it yet because I don't have another mobile phone but it is indeed a good idea to use other phone for wallet. Base on previous post about someone (theif) breaking in to your house and steal yoir gadgets left at home is to create a hiding place for your phone to hide and It is possible to do so just make sure it is hard to notice that there is a hidden compartment.

Using a mobile as a full mobile wallet may be a far better idea. I exploit a mobile wallet and therefore the number of lost and stolen items is far lower we will easily hide its information and make the transaction much easier. I can transact from anywhere I would like.


Title: Re: Using mobile phone as a full mobile wallet
Post by: kalihunter on April 26, 2022, 02:33:00 PM
thanks for your guides. hardware wallet is expansive Ledger and trezors.

what about to use any linux distro on Virtualbox as cold wallet? u can turn there off internet forever. Is that good?


Title: Re: Using mobile phone as a full mobile wallet
Post by: Mpamaegbu on April 26, 2022, 03:21:46 PM
Well, I don't see much of a hassle with using a phone as a mobile wallet if it hodls less than a single Bitcoin. All this talk about safety of funds and wallets depends on humans using them and not on the apps. It's the way I see it. People got to be very careful and mindful while at it. I don't see why anyone hodling an appreciable amount of Bitcoin on their phone should not be weary of links they click.


- My advice for you is to try as much as possible not to save your private key on your e-mail.
Who does that without expecting to reap the repercussions of their thoughtless and needless act? Surely, the penalty always comes.

Quote
- write down your private key on a piece of paper. Don't write it down letter for letter, try and add some few extra letters so as to avoid someone using it in your absence...
Smart move.


Title: Re: Using mobile phone as a full mobile wallet
Post by: Daodex on April 26, 2022, 03:33:12 PM
Cold storage is nothing without a secured private key, using another mobile phone for storing your keys or transacting a payment won't be secured enough, this still can be hacked, forget this idea and buy a hardware wallet, the hassle will be less.


Title: Re: Using mobile phone as a full mobile wallet
Post by: DdmrDdmr on April 26, 2022, 03:43:37 PM
<…>
- write down your private key on a piece of paper. Don't write it down letter for letter, try and add some few extra letters so as to avoid someone using it in your absence...
<…>
Bear in mind though, that the words that are actually acceptable are delimited to a list of 2048 words (https://github.com/bitcoin/bips/blob/master/bip-0039/english.txt). Although adding a few characters to words may seem to disguise it a bit better, someone capable of contrasting against the list will likely spot the extra added characters.

Additionally, if they were to be added as trailing characters (i.e. act-> acted; action-> actionable), there are wallets (i.e. Ledger) that will guess the word based on the first few characters you input for each word.

All in all, even though it could be an extra measure, it may not really deem effective really.


Title: Re: Using mobile phone as a full mobile wallet
Post by: cheezcarls on April 26, 2022, 04:57:25 PM
This could be so hilarious but I just need you to contribute.

If someone has two mobile phones, deciding to use one as a mobile wallet. To me, this is a good idea as one of the phones can be useless. And having in mind to use it as wallet and putting these in consideration.

Having back up of his private keys or seed phrase.
Not using it to go online but online while making transactions
Still install anti malware against malware

So, he use the phone only as wallet and for crypto transactions. So, what do you think. Is this a good idea?


If I were you, it's better to invest in a hardware wallet to store your assets. It's a lesson I've learned so hard after my 3 Metamask/Trust Wallet accounts have been hacked due to the malware that I didn't know and it was a costly mistake in my part for felling off in the hacker's antics.

Right now when I do transactions using my Metamask or Trust Wallet, I only left a few dollars for each blockchain (e.g,  Binance Smart Chain, Polygon, etc.) for gas fee payments, buying certain tokens in private or presale campaigns or minting NFTs.


Title: Re: Using mobile phone as a full mobile wallet
Post by: Charles-Tim on April 26, 2022, 07:20:25 PM
Right now when I do transactions using my Metamask or Trust Wallet, I only left a few dollars for each blockchain (e.g,  Binance Smart Chain, Polygon, etc.) for gas fee payments, buying certain tokens in private or presale campaigns or minting NFTs.
Trustwallet is a mobile wallet, Metamask is a web wallet. Web wallet are the most vulnerable to online attacks.

Do not get this wrongly, this is not about hardware wallet, hardware is secure, but this is about airgapped wallet, a wallet on a truly airgapped device are one of the most safe and secure wallets, airgapped wallets are cold wallet.