(Difficulty level: Extreme. Potential reward: God tier.) So your phone's smart. And it is. And it is amazing. And it has changed our lives. But it can be better. It can be a strong phone. A strong phone isn't just smart. It's strong. Lol But seriously, my idea is a phone that has a transparent shell with hard switches that you can visibly see open and close physical circuits that connect the power source to the camera, mic, gps, etc. that way you know they cannot be remotely activated. That would be pretty strong. Include a free bitcoin wallet. Something strong ;) Now as for a decentralized cellular network. I would need someone above my pay grade on engineering to conceive what that would mean and how it would be implemented. But you would change the entire world and remake it in your own image.