WeChat Pay is ubiquitous in China, and has largely replaced all cash use. I'm surprised nobody in the US is worried about Facebook surveilling their financial transactions.

Most people leave their transactions on public in Venmo, hence http://www.vicemo.com/

I leave mine on Public too.

And I'm surprised no one in China is worried about the government surveilling their financial transactions.

What transaction rates does WeChat Pay charge and how do they compare to Stripe/BrainTree/PayPal?

If you are just using WePay for buying food, as a customer you don't pay anything extra. For store owners, let's say a small shop that sells breakfast buns, the money to pay through WePay is usually sent directly to the owner's WePay wallet.

that’d be illegal in the US, right?

Because for the vast majority of Americans, convenience trumps privacy.

I use Zelle as first choice, venmo only after, here in US. In India, I and almost everybody uses UPI.

Is UPI in India tied to apps such as Paytm etc? or is it in itself is an app? What is the security and privacy aspect of using it?

No, Paytm is like Paypal, anybody using it need to have Paytm account.

UPI is Unified Payment Interface; sort of RSS but two way, anybody can make client for it, UPI never holds money, Clients connect to user's bank accounts (any bank); client send & receive money to/from bank accounts only, but UPI streamlines this, its kind of hub, but money flows direct between two accounts.

Most banks offers their UPI clients in their main app. A user need a bank account & then he can either signup on his bank app like SBI HDFC AXIS or any common app like Google Pay, Phone Pay. The username is like email address, user@bank style. Only banks offer the part after @. Amazon uses @abl, phonepe uses @ybl.

Once you type in user@bank in any client, it fetches the current official name of user. UPI does not hold the info, but gets it in real time from @bank.

What about Apple Cash?

Though nearly all of my frequent contacts have iPhones, none of them had Apple Cash set up before I sent them money with it. Venmo seems much more popular.

They... did.