So much cooler than hot wallets. Hot wallets are those that use an internet connected device to generate private keys, which, since they are from the internet, can't be considered 100% secure.
Hardware wallets store your private key digitally and generate them offline, making them, probably the most secure method. Since the keys are generated offline you can even use them on an infected computer and still not have any security issues.
Hardware wallets come in all shapes and sizes, some big, some small, some with a screen, and some with none at all. They have the security of a paper wallet, they are nearly impossible to breach and the functionality of other wallets in that you can easily send and receive bitcoin.
Ledger Nano S
The absolutely impressive predecessor to the ledger blue, giving TREZOR a run for its money. The Nano s has a newer sleek design, easy-to-use interface, and supports a wide range of altcoins, even dogecoin, and the list is growing. The Nano has a built-in O-LED screen and offers a laundry list of features, including easy backup, companion apps, and the ability to set a pin for added security, to top it off the Nano has a very attractive price tag, costing less than most other wallets (~€58). Ledger wallet is the company behind the Nano S and has gained the trust of users for years and has gone from runner-up in the hardware wallet to number one. You'll see this wallet in almost every top 3 list.
The Nano S' bigger brother, literally. This powerhouse of a wallet features a 3.5-inch display as well as battery power as well as Bluetooth so you can use it with your phone while you're on the go pretty much anywhere. The Blue has fully isolated enterprise-level security meaning your coins will be more secure than the gold at Fort Knox. With easy App integration, back up and added pin security this powerhouse has it all but it'll cost you (~$650) It's safe to say this is for people or business that are serious about the security of their coins.
The original and probably the most popular wallet to this day. Created by Satoshi labs, this is one of the most trusted and secure wallets on the market, it'll still cost you (~$100). TREZOR offers a wide range of support for all the most popular coins and features a small display screen and 2 buttons for pin verification, confirmations, and updates. TREZOR can also be used for 2FA, as a password manager, and be used for document signing.
Recently purchased by Shapeshift, a Crypto Startup. Slightly bigger than the Nano S or TREZOR, the KeepKey wallet comes in an anodized aluminum case, has an O-Led screen for verification and confirmation. A cool feature is the ability to connect to the Shapeshift exchange more securely, the ability to create a custom firmware, and storing multiple keys for different coins.
Unlike the other wallets listed so far, the HW.1 doesn't have a built-in screen, instead, it is an HD Bitcoin USB wallet. The HW.1 needs to be set up using a computer or a device with a USB port and screen. It's best to do the initial set up on a computer that isn't connected to the internet or a bootable operating system to ensure that the key is secure.
It is really up to you to figure out what you need from a wallet since most now support nearly every con on the market. If it is an extremely affordable wallet you are looking for the HW.1 may be your best bet, but if you a running a business or trading excessive amount of bitcoin then the Blue may be the way to go. For the more casual users, the Nano S and KeepKey are great and boast a ton of features.
What is the Best Hardware Wallet?
Regardless of which wallet you decide to go with it is important to set them up on either a bootable offline operating system, which you can purchase through most of the companies or on an isolated computer that isn't connected to a network. Most believe having a wallet with physical buttons and a screen is also extremely important, so you can verify you are sending the right amount to the right address and have to physically press a button to confirm, eliminating the risk of someone sending themselves coin through a compromised wallet. Having a pin created during set up is also important, most wallets require you to insert the pin, if the wrong pin is inserted, with the TREZOR, the refresh time between guesses multiplied by 2 each time, meaning, if someone steals your device they may have to wait years to try again. The Ledger wallets delete the data after a certain amount of wrong entries.
Don't worry though, most make it pretty easy to recover your data to put onto another wallet, as long as you have the 24-word passphrase that was created during the initial set up.