Yes, it’s possible to cancel a transaction before it gets confirmed by the blockchain by using ZenGo’s Stop feature.
To do so, go to the activity list, then tap a transaction to see its details. If it’s still pending, you should see a Stop button at the bottom of the screen. Tap it to stop the original transaction.
The original transaction should be refunded to your wallet, minus the additional network fees* required for stopping a transaction.
Works for BTC, ETH, and ERC20 tokens. Note that once a transaction has one confirmation on the blockchain, it is no longer possible to stop it.
*Network fees change over time based on network conditions and are not paid to ZenGo.