To deposit USDC from an external wallet or an exchange, you can deposit it directly into your fomo account.
In the app, go to Deposit, tap Crypto, and select the network your USDC is on. fomo supports USDC deposits on Solana, Base, BNB Chain, Monad, Ethereum and Arc, and USDG deposits on Robinhood Chain. The app shows a deposit address for that network, with the minimum where one applies. Copy the address and send from your wallet or exchange.
The Hyperliquid row in the mobile list funds your perps account, not your cash balance.
What to send
Two things to get right: to add to your cash balance, send USDC (USDG on Robinhood Chain), and send it on the same network the deposit address is for. Other tokens you send arrive in your wallet as tokens, not cash.
If you hold USDC on Base, select Base in the fomo app and send on Base. If you hold USDC on Solana, select Solana and send on Solana.
Sending on a network fomo does not support means the funds will not appear in the app. All the EVM networks share one deposit address and Solana has its own, so USDC sent on a different supported EVM network still reaches your wallet and is credited once it clears that network's minimum.
Robinhood Chain
Robinhood Chain works differently. Its deposit asset is USDG, not USDC. Select Robinhood Chain in the app, send USDG on Robinhood Chain (minimum 0.50 USDG), and it converts automatically into your Solana USDC cash balance. Do not send USDC to Robinhood Chain, and do not send USDG on any other network.
When the deposit shows
A Solana deposit shows in your cash balance once the transaction confirms, usually within seconds to a few minutes. On the other networks the funds land in your wallet first and move into your cash balance while you are signed in to the app, once the amount clears that network's minimum.