Today I received my three OpenDime (opendime.com) devices in the mail, which came from Toronto via the Coinkite headquarters. I decided to give the product a review for all you Bitcoin.com readers to get an inside glimpse on how the device operates.
OpenDime: The First Hardware Bitcoin Bearer Bond
The package I received was small and contained three OpenDime devices, instructions, and a sticker. I took one of the devices out of the packaging, noticing that all of them were sealed properly. Although the devices are inexpensive — costing just $40 USD for a three pack — the OpenDime looked very well built.
The next step was to plug the device into a USB port; green lights flashed, ensuring the device was on.
The device’s light pattern also enables users to verify whether the instrument has been unsealed. The specific OpenDime that I plugged in had not been used before, and I opened the index file associated with the hardware wallet. As a MacOS user, my file was found under /Volumes/OPENDIME and it could also be seen on my desktop as a separate drive.
After accessing the index file, my screen gave me instructions from the file’s URL. The welcome page told me that my device was new and unused, and gave me steps to generate a random key.
I was instructed to copy files into the drive itself equaling to at least 256K bytes. This can be anything from a random text file or a picture; the files are not saved on the device after completion. The wallet uses the data with a random number generator that created my public key.
After adding one photo to the OpenDime volume drive, the light blinked on the device very quickly and ejected itself. My Mac gave me a warning that the device was improperly removed, I ignored it and refreshed the URL I used from the beginning of the process.
Immediately after the page had reloaded, I had a Bitcoin address and QR code that was tethered to that specific OpenDime.
Most Bitcoin wallets and block explorers can verify the unique message to ensure everything is proper. OpenDime can check the balance of the address, and it also offers a variety of public block explorers as well. This includes Blockchain.info, Blocktrail, Blockr.ioCoinplorer, LocalBitcoins, and BitInfoCharts. After my public address and QR code was revealed, I sent some bitcoin to the address with ease and verified that the transaction went through.
Spending bitcoin from an OpenDime requires popping out the middle bar located on the device that has a padlock symbol on it. After doing this, I simply plugged the device back in this time the private key is revealed on the desktop screen. After breaking the circuit, the data is immediately altered and can never be reversed back to its original state.
I personally thought the product was very simple to use, and the instructions were easy to understand. Being the first Bitcoin bearer bond stick, I think the developers at CoinKite did a good job with this product, and I can envision many use cases. An OpenDime acts like cash and could perform a broad array of ‘off-chain’ transactions.
Some downsides are that it’s awfully small and could get lost very easily. Another downside is the circuit breaking or unsealing of the device may confuse people using it for the first time. There is also no screen on the device, which may be a problem for some users.
The “Bitcoin stick” can also be used with a phone that can access read-only USB devices. Overall I give the OpenDime product two thumbs up and will be testing the small devices and sending some bitcoin to my friends in the future. The simplicity and ease of use that OpenDime offers should be fairly simple to understand, even for a novice.
— OPENDIME ™ (@OPENDIME) April 15, 2016
What do you think about the OpenDime “Bitcoin Stick”? Have you tried the device yet? I’d love to hear your opinion about the product in the comments below.
Images courtesy of Jamie Redman