The test I use to understand most "but with Bitcoin!" ideas is simple: imagine the application "but with dollars". In this case, 21 isn't using Bitcoin is some

The test I use to understand most "but with Bitcoin!" ideas is simple: imagine the application "but with dollars". In this case, 21 isn't using Bitcoin is some way that makes it substantially different than what could already be done. If a person wanted to, they could create an API marketplace just like this, and charge 1 cent, or fractions of a cent, per transaction. Rather than turn your computer into a bitcoin mining botnet node, you load your account with a larger credit card payment to pay for it. Meanwhile, the marketplace collects the fees and distributes it to the various API owners' accounts, which can then be withdrawn once the account reaches some threshold, say $5. Here, 21 is essentially doing the same thing. Although they discuss being able to do on-chain or off-chain transactions, putting a tx on the blockchain for every $0.01 zipcode lookup is completely ridiculous and the success of such an application would essentially gridlock the blockchain, so accomplishing these types of micropayments has to be done off-chain. They're ultimately acting as a middle man between payer and payee, just like most fiat marketplaces are. 21's strategy doesn't seem terrible if you make a lot of assumptions about what role Bitcoin will play in our future. I personally think they're substantially off-base and that a world where devices have to constantly mine Bitcoin and send and receive micropayments to accomplish trivial things seems like more of a burden than a benefit. I should also say that you have to think quite a bit about what 21 is doing and make a lot of additional assumptions on their end in order to even say their strategy looks good. So far, they've released a very expensive Raspberry Pi with a hideous miner attached to it and this API marketplace where their featured API is a $0.01 zipcode lookup. I've been working on a side-project that requires me to do lookups on zipcode data and it took me all of 10 minutes to download that for free from the internet and drop it into a database. I get that they're trying to ship, but why no ship with something people would actually want to use?