TANGEM WALLET: An Innovative Seedles Cold Wallet Setup

[fillippone]

I am glad to see that Tangem hasn’t been hacked yet.
In this AI bloodbath, resilience is already a success, especially given the number of formerly reputable firms that are now unusable, like Ledger and CoinKite , for example.

[Meuserna]

I am glad to see that Tangem hasn’t been hacked yet.
In this AI bloodbath, resilience is already a success, especially given the number of formerly reputable firms that are now unusable, like Ledger and CoinKite , for example.

Tangem isn't fully open source, so the only ones who get to see the full code are Tangem and the thieves using AI to reverse engineer it.

I understand the appeal of having a wallet on a card, and for small sums only I may eventually do it. But never with anything that isn't fully open source. I'd go with Satochip instead.

I also would never trust a "seedless" approach. Seed phrases give you human readable backup to prevent your coins from being lost if the cards are stolen or lost.

[satscraper]

I am glad to see that Tangem hasn’t been hacked yet.
In this AI bloodbath, resilience is already a success, especially given the number of formerly reputable firms that are now unusable, like Ledger and CoinKite , for example.

Firmware is closed source and is loaded into the SE during manufacturing, so there’s nothing for AI to analyze to find flaws.

Besides the Samsung EAL6+ certification and the card-based design ^{which removes several attack paths traditionally associated with easy-to-open case wallets},the NFC-based air gap and other factors also played the positive role in that.

[Pmalek]

I am glad to see that Tangem hasn’t been hacked yet.
In this AI bloodbath, resilience is already a success, especially given the number of formerly reputable firms that are now unusable, like Ledger and CoinKite , for example.

Tangem is closed-source. The AI bloodbath you mentioned targeted open-source projects and those with publicly available code that can be analyzed and abused. Tangem can't be. Neither can Ledger. Not by trying to find vulnerabilities in their codebases at least. Coldcard is a different story, though. They became a victim of AI probing.

I also would never trust a "seedless" approach.

Tangem can operate in both seedless and standard (with seed) mode if I am not mistaken. Users have a choice which one to use.

[satscraper]

Latest big update for Tangem, namely version  6.5 and welcomed feature in it, i.e. for now on I can choose my own slippage before making the swap,  They also promise  if swap fails ^{when using cross-chain swapping} my money goes back to mine wallet. Tangem rocks, really.

BTW, I have noticed that sometimes the use of  cross-chain for swapping suggests better price than just direct swapping by CEX.

[Pmalek]

BTW, I have noticed that sometimes the use of  cross-chain for swapping suggests better price than just direct swapping by CEX.

There isn't one agreed-upon rate that CEXs swap cryptocurrencies at. Each CEX uses its own liquidity and has a (slightly) different rate than the next one. Cross-chain swapping services aren't limited in the same way. They can use multiple liquidity pools and trading routes. They can look and swap in multiple places to give you a higher amount if there is a big enough market and liquidity.

The rate isn't always going to go in your favor, though. Especially if there isn't much liquidity. And because it's cross-chain swaps, you also have to account for slippages, network fees, maybe bridge fees, and other costs.

[Meuserna]

I also would never trust a "seedless" approach.

Tangem can operate in both seedless and standard (with seed) mode if I am not mistaken. Users have a choice which one to use.

Users have a choice, but the way they have to enter the seed phrase is poison. No one who cares about the security of their Bitcoin should ever enter a seed phrase on a phone.

Also, Tangem's use of the word "seedless" is flat-out wrong. What they actually mean is "without a seed phrase." Tangem's so-called "seedless" wallets do use a seed. They don't use seed phrases, but they do have a seed. That's how deterministic Bitcoin wallets work. This is basic Bitcoin wallet stuff. The fact that Tangem intentionally uses misleading terminology makes me trust them even less than I already do. And I don't trust closed source firmware.

A seed phrase gives the user human readable entropy as a backup.

If you don't use a seed phrase with Tangem to generate the seed, you have no human readable entropy for your wallet backup. That's dangerous. But worse than that, you have no ability to prove the entropy Tangem uses to generate the seed is truly random or even safe. ColdCard proved why that matters, because their entropy was trash and their users got robbed.

And somebody is going to read this and still not understand that Tangem's supposedly "seedless" wallets do, in fact, have a seed, because Tangem's terminology gets in the way of people learning Bitcoin basics instead of helping.

[Pmalek]

Also, Tangem's use of the word "seedless" is flat-out wrong. What they actually mean is "without a seed phrase." Tangem's so-called "seedless" wallets do use a seed. They don't use seed phrases, but they do have a seed. That's how deterministic Bitcoin wallets work. This is basic Bitcoin wallet stuff. The fact that Tangem intentionally uses misleading terminology makes me trust them even less than I already do. And I don't trust closed source firmware.

Right. There is a seed and private keys. You need them to sign transactions and send bitcoin. What they decided was not to turn that key into the human readable string of 12/24 words that we know as recovery phrase. People seem to think that's a good idea because of the way Tangem is selling it. They are not giving you a seed phrase, so there is no backup that you can lose, misplace, or have stolen. You can't take a photo of your seedphrase, you can't store it in your email, cloud, or somewhere on your phone or computer. Sounds good at first until you realize that you have to rely on the Tangem smart cards. Only they contain copies of your seed. You can't make one independently.

[5W-KILO]

I've been doing some research on this Tangem wallet, I am trying to come up with al alternative to my airgapped device, you know, the don't put your eggs in one basket advice?

Since this wallet is a seedless one, what do you think could happen if one day Tangem wallet is no longer a thing? Like the plan to move on and never look back.

Since people don't have access to their seeds wouldn't this causes some panic if Tangem no longer works? I remember using Copay wallet some years ago, when I came back they have stopped working but I was able to import the seed into another wallet to move my Bitcoin.

[satscraper]

I've been doing some research on this Tangem wallet, I am trying to come up with al alternative to my airgapped device, you know, the don't put your eggs in one basket advice?
.

Since people don't have access to their seeds wouldn't this causes some panic if Tangem no longer works? I remember using Copay wallet some years ago, when I came back they have stopped working but I was able to import the seed into another wallet to move my Bitcoin.

This question has been asked many times, and the Tangem team has responded to it themselves i.e. If Tangem went away tomorrow, your cards could still work with any compatible app developed  by someone. Developing such app could be very easy task as  app code is open source and transactions go straight to blockchain nodes.

Besides, Tangem is not wallet to keep large sum. In my view it is for on-the-go spending. I dont keep there more then $1000 at once.

And at the very least, you have the option to use SEED mode when initializing Tangem. ^{I did it myself.}

[fillippone]

Besides, Tangem is not wallet to keep large sum. In my view it is for on-the-go spending. I dont keep there more then $1000 at once.

This is something that we have said many times on this thread, yet it is one of the most underrated pieces of wisdom.
You don't need a multi-vendor multisig setup for 1,000 Euros.
Just like you keep your earring on the top of your desk, while you keep a gold bar in a bank vault.
Different value-at-risk calls for different custody models.

[Pmalek]

I've been doing some research on this Tangem wallet, I am trying to come up with al alternative to my airgapped device, you know, the don't put your eggs in one basket advice?

What exactly draws you to the Tangem? If you want something with smart cards, there are other options. Open-source ones. For example, Satochip. Or Keycard and Keycard Shell. If Tangem disappeared tomorrow, you wouldn't necessarily lose your coins, but you depend on someone to build a usable app for you. Maybe you can or want to do it yourself. If not, you'll have to wait a week, a month, a year... until you will be able to spend your bitcoin. That doesn't seem very attractive to me.

[satscraper]

I've been doing some research on this Tangem wallet, I am trying to come up with al alternative to my airgapped device, you know, the don't put your eggs in one basket advice?

What exactly draws you to the Tangem? If you want something with smart cards, there are other options. Open-source ones. For example, Satochip. Or Keycard and Keycard Shell. If Tangem disappeared tomorrow, you wouldn't necessarily lose your coins, but you depend on someone to build a usable app for you. Maybe you can or want to do it yourself. If not, you'll have to wait a week, a month, a year... until you will be able to spend your bitcoin. That doesn't seem very attractive to me.

Tangem Pay could be the answer. No other HW designed in the card format offers similar functionality. Regarding disappeared-tomorrow-lose-your-coins  that argument is not applicable here because as I said in my previous post Tangem has the option to be initialized with SEED. So users are free in selection what mode to use.

[fillippone]

I've been doing some research on this Tangem wallet, I am trying to come up with al alternative to my airgapped device, you know, the don't put your eggs in one basket advice?

What exactly draws you to the Tangem? If you want something with smart cards, there are other options. Open-source ones. For example, Satochip. Or Keycard and Keycard Shell. If Tangem disappeared tomorrow, you wouldn't necessarily lose your coins, but you depend on someone to build a usable app for you. Maybe you can or want to do it yourself. If not, you'll have to wait a week, a month, a year... until you will be able to spend your bitcoin. That doesn't seem very attractive to me.

My reason to use Tangem:

• Totally anonymous credit card form factor in my wallet
• Innovative “seedless” custody approach. Peace of mind of seeed backup via physical cards. Worth a try for pocket money.

In my opinion, Keycard is the best substitute, if you really hate closed source (totally legitimate position).

[Meuserna]

My reason to use Tangem:

• Totally anonymous credit card form factor in my wallet
• Innovative “seedless” custody approach. Peace of mind of seeed backup via physical cards. Worth a try for pocket money.

Why would you want to not have a human readable backup of the seed?

As explained earlier in the thread, Tangem's use of the word "seedless" is bad marketing. Your Tangem wallet does have a seed, generated from various data from the card itself (none of which you can prove to be truly random, which is exactly what led to ColdCard users being robbed). What a Tangem "seedless" wallet doesn't have is a seed generated from a seed phrase.

I think Tangem's terrible marketing leads to people not understanding their Bitcoin wallets (I'm not saying you don't understand your wallet actually does have a seed. I'm making the broader point about misleading marketing terms).

[fillippone]

Why would you want to not have a human readable backup of the seed?

The main reason is that removing the hassle of the backup of the words, using the card as a backup, might give the user a better experience, without worrying for those words spread somewhere.

[Pmalek]

The main reason is that removing the hassle of the backup of the words, using the card as a backup, might give the user a better experience, without worrying for those words spread somewhere.

Proper seed/keys backup has always been an integral part of Bitcoin and being your own bank. I don't want that to change, and I don't want people thinking that it's ok for Tangem to be the bank instead of the user because that's easier for them. It's even easier to use an exchange for everything but we have learned through the years how terrible that is and have seen many examples of things that can go wrong. I am not comparing Tangem with an exchange btw. I just wouldn't want simplicity to become the reason for not doing the basics like proper keys management.

[Meuserna]

Why would you want to not have a human readable backup of the seed?

The main reason is that removing the hassle of the backup of the words, using the card as a backup, might give the user a better experience, without worrying for those words spread somewhere.

I say this with all due respect.

If somebody thinks writing down seed words is a hassle, they're too lazy to secure their financial future. It's fine if they're just playing with a little money. But anybody who thinks of Bitcoin as a way to be their own bank needs to think about what it takes to be your own bank. Your security is your job.

Not having access to the entropy that generates your keys isn't innovative. It's reckless.

I understand the idea that a credit card-style card is convenient, but it's terrible for security if the card is blind signing. Every transaction is blind-signed. If you don't know what that means, learn about it, and understand the risks. "But the app shows..." The signatures aren't generated by the app. "Right, but the app shows..." That means trusting code on the app to trust code on the card, which is multiple layers of bad since the card shows nothing.

Worse still, you don't have access to the entropy for your wallet, which means you have no human readable backup. That's really dangerous, for many reasons. And it's closed source, which means you have no way to prove the firmware is safe other than by trusting a company, which defeats the entire spirit of Bitcoin and being your own bank.

[fillippone]

Proper seed/keys backup has always been an integral part of Bitcoin and being your own bank.

I say this with all due respect.

I fully understand your position, and I also respect the thinking behind both of those.
I wouldn’t be a self-custody maxi and a privacy maxi if I didn’t agree with that.
What I think differently is that for small amounts of Satoshi, I am willing to exchange trust for convenience.
Tangem wallet and custodial Lightning apps are a good compromise for small amounts if they improve the user experience of Bitcoin.
I don’t see how using a custodial service (yes, even an exchange) to use a small amount of money can hinder the properties of Bitcoin.

[Meuserna]

Proper seed/keys backup has always been an integral part of Bitcoin and being your own bank.

I say this with all due respect.

I fully understand your position, and I also respect the thinking behind both of those.
I wouldn’t be a self-custody maxi and a privacy maxi if I didn’t agree with that.
What I think differently is that for small amounts of Satoshi, I am willing to exchange trust for convenience.
Tangem wallet and custodial Lightning apps are a good compromise for small amounts if they improve the user experience of Bitcoin.
I don’t see how using a custodial service (yes, even an exchange) to use a small amount of money can hinder the properties of Bitcoin.

Small amounts. Yes. We're in agreement. Personally, I still wouldn't use Tangem since it's closed source, and blind signing (which is what Tangem does) comes with additional risks... not to mention the device calls itself seedless even though it uses a seed but it doesn't give the user access to the entropy. That's bad in so many ways...

But, yeah, for small amounts, I understand favoring convenience over maximum security.

Too many people don't understand the risks though, and they're using things like Tangem or even exchanges to hold large sums of Bitcoin. I wish we, as a community, did a better job of helping people understand risks and best practices. Even many devs don't follow best practices because their goal is to sell products like Ledger or Tangem.