Hi, after some extensive research, the exact temperature is 75.5℃ for the iPhone (most likely for other Apple products too like the iPad), for the glue/water-proofing to soften so it can be pulled up.
75.5℃ from Apple Repair Tools Itself
0.08mm string to help separate just the glass form any cellphone's LCD
The expensive stylish armor cases (unless it's those really thick cases built for the wet outdoors) & expensive tempered glass doen't work against pavements, even if the fall is just waist height, especially against parking lot pavements (which has sharper surfaces), if this glass only replacement is successful w/ relatively cheap non-pro tool like those in the link above (I will turn off all fans & close all windows to prevent dust as much as possible), I can finally leave this iPhone and future iPhones without any case so the aesthetic in it's design with the thinness will always be seen (not hidden with a case), I'm also planning a non-destructively mod the iPhone inside if it that's possible, God-willing, to make it hopefully always fall and hit the ground at a certain spot all the time as much as possible away from the screen and impact-sensitive modules like the camera.
May this help with everybody's future revival of Mac products (alleviate pollution as well with some time sacrifice repairing things- carbon neutrality).