I thought they are using business plan: https://mobile.twitter.com/eastdakota/status/692143735157710849

Invoice-based billing

Pro and Business plans are billed using credit cards. Enterprise customers will receive a monthly invoice

To my question, can you explain at a high level or in laymen terms what makes zcash more anonymous or untraceable than bitcoin? What properties does it have and how is it able to achieve anonymity?

The high-level answer is like this:

Bitcoin is a global, shared, append-only ledger, right? And so is Zcash. The entries that get appended to that ledger — the transactions — basically say "From Address", "To Address", and "Amount Transferred". The difference between Bitcoin and Zcash is that in Zcash those three values are encrypted, so that they aren't publicly readable by default.

(The person who made a transaction could still make it be publicly readable, by publishing the decryption key, or could share the decryption key with selected parties to make it readable to them without making it readable to the world. That's what we call "selective transparency".)

So far so good.

Now the cryptographically challenging part is: how do we enable the miners and full-nodes to reject invalid transactions? This is where the zero-knowledge proofs come in. With zero-knowledge proofs, the creator of a transaction can include a proof that the transaction is valid (i.e. isn't a double-spend) without revealing anything about the encrypted "From Address", "To Address", or "Amount Transferred".

@krakenfx let's get the facts straight. Credit card provided for payment expired. After 3 warnings you were downgraded to a free account.