Multisig is hard, cold storage is hard, MPC or keysharding is hard.
ExtraSafe is extra easy.
By connecting an iPhone/iPad to a raspberry pi, we can separately generate private keys, deploy safe contracts, and run the required infrastructure to run the wallet.
To run a gnosis safe, not only do you have to deploy the contracts but you also have to run the transaction monitoring hardware for each chain the safe is deployed to, we make all of this simple by running all the required daemons on a seperate piece of hardware that when not powered in effectively in cold storage.
We started with Gnosis Safe, the safe transaction service, and the safe configuration service. Porting those to ARM64 and getting docker to properly run on a small device. WalletConnect 1.0 is used to link the mobile application to the raspberry pi. IPFS is used to store backup copies of the keys.