I can't sign offchain transactions using the standard https://eips.ethereum.org/EIPS/eip-712
It happens in IOS.
Also, tried using the desktop application connected to the IOS wallet, and it also fails.
How to reproduce
I can provide Rinkeby tokens if it helps reproducing the issue.
- Go to http://cowswap.exchange
- Connect (injected wallet). Note, the app works in mainnet, but also Rinkeby and xDAI
- Select any token pair
- Approve sell token for selling
- Try to swap. Swapping signs the transaction using EIP-712