What would happen if Casa got removed from the App Store?

You can use Sovereign Recovery, but you can also turn off app deletion on iOS devices. Here's how:

Settings > Screen Time > Content & Privacy Restrictions > iTunes & App Store Purchases > Deleting Apps > Don't Allow

We recommend doing this in advance. Read more about Sovereign Recovery here: https://support.casa.io/knowledge/sovereign-recovery-for-bitcoin-vaults