All the phones we tested showed themselves to be pretty tough. The iPhone 6 Plus, the more robust of the new iPhones in our testing, started to deform when we reached 90 pounds of force, and came apart with 110 pounds of force. With those numbers, it slightly outperformed the HTC One (which is largely regarded as a sturdy, solid phone), as well as the smaller iPhone 6, yet underperformed some other smart phones.
Note the 6 Plus performed better than the iPhone 6, which is honestly just kind of weird. Still, while the 6 Plus (and the 6) isn't as un-bendy as some competitors, it also isn't the Gumby-like slice of soft cheese that some media narratives would have you believe.