Let's say I own a smart home ecosystem and a mobile app that users can use to turn on their air conditioner.
Is there a way to incorporate blockchain so that no one else can turn on that air conditioner besides the whitelisted user?
1) If I put the private key as a config in the app itself, is that dangerous? To my knowledge, having the private key allows the app to sign my transactions allows me to safely with my smart contract. But does that make my app hackable?
2) One concern I have is that it would be too slow to mine the transaction. No one wants to wait a minute to turn on their air conditioner.