Even my five+ year old phones are in perfect condition, despite their primary users being my toddlers now.
Although I don't use iPhones (Androids).
From the old indestructible Nokias, passing through a Sony Ericsson, a Nokia Windows Phone, and then the Moto G4. Until my previous phone.
My previous phone was a Moto G6, with glass in the back. In the second day, it fell from my lap and the back-glass broke completely, but stood in place with glass dust all over. I had to use a case (that is shipped with the phone, probably predicting this). I was pissed, always hated. All of that because of a useless aesthetic product decision.
Then I bought the latest iPhone SE, my first iPhone ever. I use it without a case and it fell, from various heights, probably more than 30 times now. The screen is intact, just a few scratches in the corners. I am pretty happy about it.
Edit: just in case anyone wants to know, I don’t like cases solely because it makes the phone larger. The “how easily and comfortably it fits in my pockets” is my main criteria. I don’t care about aesthetics much, consequently I also don’t care if my phone has scratches on its sides. That’s one reason I changed to the iPhone SE (small phone + great chip + privacy considerations). I would only ever consider buying the iPhone Mini out of these iPhone 12 line.
The 12 seems to be similar to the 5 (and the iPad Pro), so let's see if it's any better to use without a case.
And easier to crack the screen when it lands on the edge. I'm pretty sure I didn't drop my 6S more times than I dropped my iPhone 5 or 4S, but I cracked my 6S screen three times, whereas I never cracked my 5 or 4S screens at all.
The glass repair guy down the street must love me.
If it really protects the phone like they said it will (even 2x, not 4x) then this would be a revolutionary upgrade for me.
The iPhone 8 with it's full-glass enclosing has been surprisingly sturdy, surviving even rough drops with only a scratch. Plus if it breaks, I get two replacements with AppleCare, and the process is ridiculously smooth.
I occasionally drop it from my pocket onto not-too-hard ground without damage and I bent the corner a bit dropping it on tarmac when I was drunk once but otherwise it’s unscathed. Maybe I’m just super lucky.
From my first day of using them together all I could think was "I want this connection method on every tablet and phone"
Also, btw, the iPhone 12 MagSafe doesn't prevent you from using a case.
However when carrying the phone in my pocket or bag I always use a fabric sleeve with microfiber inner lining. To me this approach is the best of both worlds: The pure device when in use, but protection when carrying it around - Plus, instead of having to put the device down on hard surfaces the sleeve serves as a soft bed for the phone. And the microfiber lining keeps the display clean.
All my past iPhones looked pretty much pristine when I sold them on ebay.
Did the same for my 6S, and cracked the screen three times. The third it cracked time I upgraded to an iPhone XS; but my wife insisted I get a case, and it was hard to argue against.
I'm really glad they've moved back to the (apparently) more robust form factor of having squarish metal edges. I look forward to not having to use a case the next time I update.