In most part of Africa hardware wallets are not only difficult but expensive to get apart form using custodian wallets like trust wallet and metamask is there an alternative software that can help hodl Bitcoin in a flash drive. or otherwise
Well you can created a bootable OS on a flash drives, like Linux or Windows.
You can verify the IOS version of trust wallet here:
https://github.com/TrustWallet/trust-wallet-ios. But as far as I know it's not fully open source so just be careful on using it.
And we all know that storing private keys in plaint text specially in flash drives is not a save security practices in my opinion.