To add a new token, you can do so via adding a new token contract address. The process is fairly easy. From your main wallet page, you should be able to find the search bar with text Search Coin. Inside this search bar, you will be able to see the + button. Tap it. You should see this same interface:
Once you see this same interface, you should select your preferred network. To add an ERC-20 token or other Ethereum-based tokens, the Network should be Ethereum. Then, copy-paste the token contract address to Contract Address on this page. The app will recognize the name, symbol, and decimals by itself. Tap Done and that's it.
If you want to add a token contract address on different network other than Ethereum, tap on Network and you will see a dropdown to choose other networks.
For now you will be able to add custom token contract address for Binance Smart Chain (BSC) and Tron. In the future version of the app, you will be able to add token contract addresses for other networks such as Polygon, etc.