Like you, I too won't give up my liberty for security.
In a sensible analysis of this, there's just no need for some superspy device to break into anybody's phones. We can greatly reduce crime and greatly increase personal and public safety if we just do a few things:
1. One piece of evidence all by itself will almost never put somebody away. If it's a serial killer and they're going to be put away, there will be tons of evidence from multiple sources and multiple crimes, and none of it needs to come from somebody's phone. To think that that "one critical piece" will be found on a smartphone is not only beyond simplistic; it may actually be a sign that somebody is watching too much bad network television.
2. I've said it many times. It's easy to stop terrorist attacks: Keep out the people who want to do us harm. Just don't let them in! The US has done this for dozens of decades. We should send home people who overstay their Visas. Don't allow people in from countries that hate us. Don't allow people in who have made comments in public or social media that show that they are a danger. Why do we feel the need to allow haters into our borders? Let's also require trade partners to adhere to some basic requirements.
If we do more of the right things and fewer of the dumb things, then it won't be necessary to break into people's phones to find some tiny piece of damning evidence that probably doesn't exist anyway, because those people will just be causing trouble in their own countries (or in those with lax immigration policies) and not mine!
3. There is no shortage of people who are convictable/convicted of serious crimes WITHOUT having to break into their phones. Because they get convicted! But they get off by way of weak judges and light prison sentences. Why not send them to prison for the length of time allowed by and dictated by law?
I'm not even advocating making the law stronger, no. Just make them serve their sentences in full. I'd pay for additional prison space if we could just have a court system with the b@lls to enforce current law! Anybody else willing to crowdfund a few more uncomfortable cots in the nearest supermax?
4. Stop punishing people for using violent force or deadly force in their own self defense or the defense of their families or others. This is much more of a problem in the UK, where you can get a 2 year sentence if you just pick up a stick to defend yourself from men with knives, or you get tried for murder because during his attack on you, you grabbed your home invader's weapon and happened to maim or kill him with it.
Blaming and punishing the victim is beyond stupid, but nobody in the UK can complain or they could be convicted of some kind of thought crime and still go to jail! Luckily for me, I can say it because don't live there and don't plan to visit any place where citizens are not free to defend their own lives and property. I am a free citizen in my country, not merely a subject without real rights.
It's simple. Don't let evil in your house. Or your country. And when it rears its ugly head, lock it up. And for God's sake, don't punish people for killing evil when it breaks into their house or attacks them on the street!
Most mass murders in the US are committed by socially excluded white school boys with access to guns in their family home. Is America going to throw them out to protect society?