Top 10 Frequently Asked Questions about the CoolWallet S

From CoolWallet S Client Experience Group

“As CoolWallet S Client Experience Group, we always strive ourselves to provide the best products and services.”

Q: What does CoolWallet S do?
A: CoolWallet S is a handy cold storage device for cryptocurrencies: Bitcoin, Bitcoin Cash, Ethereum, Litecoin, Ripple and all the ERC20 tokens. It has a great balance of world-class security and convenience. It is easy to carry — easy to use — simple steps — highly secure.

Q: Do you support all ERC20 Tokens?
A: Currently, CoolWallet S allows our client to add their desired ERC20 tokens as long as the tokens are correctly set up (Token Name, Decimals, Symbol, Contract Address, etc….). 
To learn how to add ERC20 tokens, visit here.

Q: Why is the firmware not open sourced?
A: We can provide source codes of the Micro Controller Unit code and firmware. As for the coding in the Secure Element chip, we will only provide access to the trusted members of the cryptocurrency communities and/or security industry to evaluate and audit all of our code and libraries.
Furthermore, a few ongoing Black Box Tests have also been conducted by multiple independent companies to perfecting our codes. Once that is completed, we will provide open source codes for our wallet. The estimated time should be the end of 2018.

Q: What if the battery inside the CoolWallet S dies?
A: With normal usage, our battery should last for more than 2 years. However, the life of the wallet battery may still be affected by temperature and charging habits. Thus, we recommend you to charge the wallet battery on a periodical basis.
However, even if the battery dies, you can still use the charger as an external battery source. Basically, you can use the wallet w/ or w/o the battery.

Q: Is CoolWallet S safe?
A: Every CoolWallet S is equipped with CC EAL5+ certified secure element, which means your private key is always safe inside it, even if it’s physically examined. Most importantly, the private key never leaves the CoolWallet S. Internet devices need to be paired with CoolWallet S and then go through a visual one-time password verification to communicate with CoolWallet S.

Q: Can I recover my CoolWallet S seed to another wallet?
A: Please note that the seed generated from CoolWallet S adheres to BIP 39 protocol
We transfer the English mnemonics into numbers so the App can help to verify the correctness of the seed quicker. This also allows you to perform a simple addition question to verify the correct seed. If you need to use the seed generated from CoolWallet S to recover on other wallets, simply look up the attached mapping table, find the corresponding English words, and type them in the wallet you wish to use.
However, with the usage of P2WPKH-nested-in-P2SH (BIP141 / SegWit) transactions, it is necessary to have a common derivation scheme. It allows the user to use different HD wallets with the same master seed and/or a single account seamlessly.
Thus, if the wallet created uses dedicated segregated witness accounts, which ensures that only wallet compatible with BIP49 will detect the accounts and handle them appropriately.
CoolWallet S is an HD (Hierarchical Deterministic), which uses BIP44 derivation, thus, your accounts may not be detected when you recover the seed on BIP49 supported wallets.
In case you are unable to find a wallet that supports the same protocol. Please refer to the recovery guides below:
BTC Recovery Guide:
BCH Recovery Guide:
ETH/ERC-20 Token Recovery Guide:

Q: What if I lose my CoolWallet S or my phone?
A: No worries. Simply use your seed recovery card, and enter the backed up seed when you recover the wallet on the app.
Likewise, you can restore your cryptocurrencies using any standard hierarchical deterministic wallet that uses the same protocol. However, we recommend that you buy a new CoolWallet S and restore your seed via our app for optimal security.

Q: Why has my wallet’s firmware update always failed?
A: Stable power source and Bluetooth connection are required for a successful firmware update. Please kindly insert the wallet into the charger and charge it during the firmware update. This should resolve the issue.

Q: Why is my CoolWallet S not reflecting the correct balance?
A: Our wallet is a complete offline wallet, it is designed to be isolated from the internet for security purpose. Thus, balances from the App will not be synchronized automatically. You will need to synchronize the balance manually using the refresh icon on the “receive” page of the App.

Q: Can I back up my wallet data on both of my CoolWallet S?
A: Yes. If you are using 2 separate phones for each of the CoolWallet S, the setup process is the same. And if you want to use the same phone to do the setup, please refer to this guide.