Zero Confirmation Acceptance

The idea is that those who accept Bitcoincash need not wait for a transaction to enter a block because a conflicting transaction will be rejected by the network. You're transaction goes throughout the network and a new conflicting transaction will not be accepted. However, it may not be the case that the one that is first for your node to see is the first transaction of the mining node to see. The transaction paying the merchant might lose the race to the miner. The double spend proof available with some APIs seems unused by any of these wallets; at least there is no claim they do use it on their websites,

Although theoretically, we can handle double spend transactions because we can recognize them and then we may ignore them, It seems wallets just don't do that.

Address Count

A wallet can take a seed phrase and take the first address creating a single address and single private key. In this case the same address is used again and again. You could have more than one of these of course. With an HD wallet, you create a master public key and a master private key and derive new addresses for each transaction from the master public key and spend those funds with private keys derived from the master private key.

Cash Fusion

Normally, each payment will use one digital coin of some value and create two digital cash units one for paying the exact amount to the recipient and the other change back to the spender. For example, if we are to pay 0.025 for something and we have a 0.15, this might be one digital coin of 0.10 and one of 0.05 (the analog of a dime and nickel). It could also be three 0.05 (like three nickels) or 15 cash units of 0.01. In the first case, the wallet can choose the digital coin of 0.05 to go into the transaction which destroys it, create a new digital coin of 0.025 for the recipient and another back to the user which will be slightly less than 0.025 for the fee to go to the miner.

With HD wallets, the 0.05 BCH would come from one address, and the smaller new coins would go to two different addresses. With cash fusion we take the original digital coins from many distinct transactions.

Cash Shuffle

Cash Shuffle essentially creates transactions to yourself using Cash Fusion. So the origin of the coins you have received is less easy to determine.

Should your Wallet be Lost

If you lose your wallet, the PIN feature protects your funds. You can even go Biometric

Multi-location keys

If your wallet is multisignature but all of the private keys are in the same place, then it is trivial. If it is multisignature and other key is on your desktop or on a server somewhere then should your wallet fall into the wrong hands your funds could still be safe.

For example, with a 2FA provider that keeps one of the private keys you might not be able to send a transaction until you enter a second factor code or tap on a dedicated signing device you keep separate from your main wallet.