You might wanna adjust the sensitivity level in this case. Whatever that you peeked at shouldn't have a problem popping when you press harder, so I'm guessing it can be a software issue or that you are not pressing hard enough.
I kinda find it weird to wanna press so hard on my phone though.. Those with iPad Air 2 are probably aware that we wanna tap as light as possible or the screen may have a ripple effect lol