[Galaxy S 4 General] puremind:
Yes, the other factors are:

reflectance value (both the One and the S4 have good values there)

ambient light: in the sun or with sky reflections, the S4 will have issues, even in third party browsers, because the black levels are not perceivable anymore - it is not summer yet :)

The S4 will be comfortable in most situations but it will not be as comfortable as the one with about only 50% brightness left during web browsing outside, and you will struggle in the brightest envonments (sunny summer day by the pool or outside walking).

---------- Post added at 01:33 AM ---------- Previous post was at 12:49 AM ----------

Thank you, it's nice to know that hard work is appreciated. I am an idealist at heart, and all I want is for manufacturers to keep improving on their weaknesses.

---------- Post added at 02:08 AM ---------- Previous post was at 01:33 AM ----------

Let me take another approach for a minute. Instead of saying why each device is great, I would like to say what I don't like about them and how they could/should be improved. I think that phones really only win where others are weak, so I find that approach a more useful way of looking at those two phones. Saying "the processor is faster on this one" when in real life the other phone does no feel inferior, is helping noone. A phone really only shines where it fixes a shortcoming of the competition!

Before I start, I would first like to say that my opinion reflects the current experience on both smartphones. Some of the current issues I am noting will likely be fixed at a later point in time.

S4

Brightness. Brightmess clipping means overall outdoor screen performance is poorfor web browsing (and the extra throttling in Chrome and the Stock browser was clearly designed to fool battery tests)

Green White Balance in Film Mode. I don't understand why the S4 is calibrated with a green push and oversaturated colors in film mode. Seeing how precise and consistent the screen calibration is on the S4, I think Samsung should have given us a more accurate film mode that doesn't spoil web browsing with a green veil.

Camera. Not as snappy with its 13MP: doesn't stabilize or focus as well. In every day use, I think HTC made the right choice with their camera. It feels more responsive and will capture anything quickly without motion blur. I recognize the extra sharpness when I zoom or crop pictures, but it takes space and resources and I personally think 8MP were enough. Focus and stabilization are so important for good pictures. Many of the camera tests missed the point in my opinion because they shot in a controlled environment.

Lags. Still some lags (I am starting to suspect this has to do with the servicess needed for dual view)

Sound. Good but not great and the speaker is backfacing and often coverered with the hand.

Cluttered software with dated design. The software layer does not feel very modern and has too many menu items at the top where they are hard to reach (e.g. in the camera)! Some controls are too small and not adapted to 1080p resolution. The dialer uses tabs instead of flowing through screens. Overall I really wish a TouchWizz refresh from Samsung. There are some areas that are better (e.g., the magnifiying glass for text selection, the word correction mechanism) but others are worse (e.g. Stock browser only has 1 zoom level and does not reflow text at custom zoom levels). I liked the cleaner and snappier Sense 5 experience better at this point, but I am counting on future developments to fix this!

Design/Premium feel. I don't think the design is ugly or cheap (the White version actually looks nice) and I don't need it to be aluminum (and please no glass), but it could have a bigger wow factor (e.g. Blackberry Z10) - that said, the ergonomy of the design should not be understated.

HTC One

Screen Size. The screen could be 5" in the same form factor - when you use both the S4 and the One, you do come to appreciate the extra real estate offered by the S4.

Ergonomy. Not as comfortable to hold overall, the S4 actually feels smoother and more natural to hold, has no hard edges. The button feedback is really not the best. Placement does not annoy me as much as the fact that the buttons are recessed, hard to press or (for the capacitative buttons) not very reactive. The S4 is really easier to handle in every day use from a hardware perspective.

Battery performance. Battery life could still be better - I am disappointed with the update or generally with the battery drain in idle mode. Since the update I feel that outside of web browsing, battery lasts longer on the S4. I haven't started to look into this to see if devs are talking about the update and how it impacts battery and what can be done to improve this. Battery life is one thing that will need time to settle, but right now I give an edge to the S4 based on my current use. I am attributing the to the poorer network reception, seeing as it gets lower LTE speeds than the S4, I find this a plausible explanation. If anyone has got information on the current battery drain, please point me to it.

LTE and WiFI network speed. About 15% slower than the S4, the antenna inlay does the job but it is clear to me that signal is still hampered through the aluminium construction. I haven't compared my own findings with official reviews, but if someone has references to share, please point me to it

MicroSD and replaceable battery. I don't think it is a big deal to most people, especially since other options with their own advantages exist, but I am going to list them here anyways for completeness

SAR level: 0.74 is a bit high

In a nutshell

The One wins in terms of style (sex on a phone), sound and software ergonomy (including camera snapiness and stability)

The S4 wins in terms of hardware ergonomy (form factor, larger screen, buttons, battery in daily use) and WiFi/LTE speed - with the notable exception of lags and in some applications.

I think the above lists say: "if you were to lose your phone and got the other phone instead, what would you miss? What would you perceive as an annoyance".

So what will I do?

Since neither device is good in all situations, I have to keep both. There are things that I like and would miss both of these phones.

For the time being, I will likely use the S4 as my daily device, because it feels more ergonomic in most situations and battery life seems quite a bit better since the HTC Update.

I will use the HTC One to watch videos (my laptop just stopped working and I am so happy I can depend on the good sound to watch the downloaded 720p episode of American Idol), as my Home Cinema remote control and when I go out on special occasions or on a very bright day (e.g. Thailand or Brazil vacation).

I will continue to monitor how firmware and ROM development evolves and see if the issues mentioned above have been fixed

Right now, I feel the S4 has more to win from Software development than the One (screen accuracy, removal of lags, better, cleaner, more modern UI) . How much idle battery life will improve on the One will be a big factor.