Cross-chain function is launched by MathWallet, it allows users to exchange assets over different chains through this module.
Download MathWallet:
https://mathwallet.org
(iOS users please download the Testflight version)
Ethereum → Binance Smart Chain
Switch to ETH wallet，click crosschain
Entering into crosschain page, choose the assets for transfer, currently it supports ETH/USDT/MATH/UNI/USDC/SUSHI/LINK/DAI
Here we take USDT as an example
After entering the amount then choose Binance Smart Chain（Currently MathWallet supports Binance Smart Chain/Solana，and more cross-chain will be added in the future）
Choose address
Click Cross-chain Transfer and wait for on-chain confirmation to complete the transaction. You can click Transfer Record in the upper right corner to check the order details.
Binance Smart Chain →Ethereum
Switch to Binance Smart Chain, choose cross-chain, then follow the same steps as above.
Note: after the Ethereum token is transferred across the chain to the destination, you need to manually initiate a transaction in the “Transfer Record” to collect it in your balance
The operation video guide:
http://blog.mathwallet.org/?p=2632