1. Two figures, and why
The network keeps a record of who holds USDT. Sending to someone who already holds some updates their line in that record. Sending to an address that has never held USDT has to open a new line, and the network charges about twice as much for that.
So a send costs 2 USDT when the person already holds USDT, and 3 USDT when their address has never held any. Most people you pay are in the first group.
2. How the fee is worked out
A send on TRON uses up a resource the network sells for TRX. The app rents that resource for your send and pays for it on your behalf, so you never buy, hold or think about TRX.
The rent moves with the network's price, so the fee is worked out at the moment you send: the live cost, a small margin for us, rounded up to the nearest half USDT, and never below the two figures above. On most days the figure is exactly 2 or 3.
The screen shows the exact fee before you approve with your face or fingerprint. The figure holds for about a minute and a half; take longer and the app works it out again.
3. What is free
- Receiving USDT, from anyone, any number of times.
- Making an address, or several under one recovery phrase.
- Saving a person's name to their address.
- Connecting an exchange with a read-only key, and reading its balance.
Nothing is charged until you send. The fee on a send is how the app is paid for, and there is nothing else: no subscription, no coin of our own, nothing about you sold.
4. If you hold TRX
An address that holds TRX can pay the network directly, the ordinary way. The app shows that route beside the USDT one, with its own price, and preselects the cheaper of the two. An address with no TRX is shown the USDT route on its own.
5. The fine print
The fee you were shown at the moment you approved is the one that applies to that send. If you do not accept it, do not approve. The rest is in the terms of service.