The order of importance for the uses of a phone have changed in the past 5 years for me.
I remember when I first thought about getting a smartphone, all I cared about was the ability to make calls. That has drastically changed over time as I cant stand talking on the phone anymore. My uses for the phone have also changed because of kids, capturing those life moments are very important to me. My parents are missing about 12 years of my life because of no pictures. It seems as I became 10 years old and the next thing you know I'm 22 and graduating college. So I have nothing to show my kids of how cool their dad was in high school. I cant show the Size 52 Jinco jeans or the year in high school when I decided that a part down the middle of my head was a good idea. They wont be able to see the slits that I used to put in my eyebrows.
On second thought, maybe this might be a good thing.
The camera is the most important feature of the phone for me. A phone that does everything well yet doesn't take quality pictures is pretty much dead to me. I need to be able to take pictures that I can use to blackmail my kids in their twenties. I need to be able to reflect on how bad they were when they try to show me up as an old man. The pictures just cant be good quality but the ease of use has be that good as well. I judge ease of use by being able to hand the phone to my seven year old. If she can figure out how to take a picture with no issues then its easy to use. The HTC One A9's camera is just that, the old Geico tagline would work here "So easy a caveman can do it".
Taking a quality picture with kids can be an exercise in futility, often times you just aren't quick enough. Once you get the phone out of your pocket, unlock the device, bring up the camera app, tap the screen to take the picture, and finally wait for the phone to focus and actually take the picture you may actually end up having a beard as long as Mithrandir aka Gandalf the grey or a better reference may be Professor Dumbledore (my geekiness has to shine through in everything I write). With the A9, one can take the phone out of the take a picture and return the device back into the pocket within a few seconds. The front facing camera uses the UltraPixel feature of the old M8 and M9. Its enlarged pixels make low-light photography an added asset. The A9 while not as good as the predecessor in low light quality pictures certainly handles its own.
These are pictures from a Christmas performance that my wife participated in. I was way in the back and in a dark room with only the stage light up. I was pleasantly surprised at the quality of the shots that I was able to take.
The front facing camera was able to allow me to capture my daughter deciding that she had enough and wanted to go to sleep. Again keep in mind that I was in a completely dark room.
Here is a video of my son recently at the park, with the slow motion feature you can see all 100 of his teeth.