The issue really isn't the phone itself for Sony (at least how I see it). Personally, I believe Sony's issue has been a lack of identity among its consumers regarding its mobile devices. Apple has an iOS and the whole ecosystem going for it, Samsung is the current champion of Android. All Sony needs to do is utilize their PlayStation OS on their own mobile devices and that should be the tipping point for Sony to be viable in the smartphone market.

Since the PlayStation brand is already a proven commodity among the mass populous and phones like the Z5 premium are stellar technological marvels that already have PS4 Remote Play capability, the move should not be that difficult for Kaz-Sensei, Shu-Sensei, Totoki-Sensei and the other sensei's to discuss upon. Sony will most likely be getting more profit than what it is now.

Just my opinion though, and I am sure I could be wrong, but Sony already has experimented with a singular ecosystem with the PlayStation brand in some capacity. I am sure expansion would not hurt; attempting to do so anyway.

If they keep making great phones, eventually they will be recognized for it and will do well. They don't need to beat Samsung or Apple, they just need to make sure the phone division is making a healthy profit.

This is exactly what Sony needs to do. PlayStation OS should be running on every TV, Smartphone, Tablet, Blu-ray Player, Camera, and gaming device that Sony sells. They should have a feeling of connectivity and similarity across the brand. This way a consumer knows what they are getting when they buy a Sony product, and they know that all of their purchases, and all of their devices work in harmony. 

Like you said, Sony has to get off of the me too OS, because S*****g already owns that market. They have to set themselves apart from the competition, and give people a reason to switch from S-Phones or A-Phones. PlayStation already has a strong ecosystem behind it, an devs already have experience with cross platform development, and cross buy. All Sony has to do is open up PlayStation Development, and allow more proffessional non gaming companies to release their apps/software on the PlayStation Store. They won't compete with the market leaders from day one, but with a little investment, and good marketing, PlayStation OS and PlayStation Hardware could be close to leading the market in the next 5 years.

i call BS on the camera thing! m§ has the best cameras!, they have THE best and their smaller smartphones have way better cameras than the small smart phones from the others

Had a Sony MP3 phone, about 8 or 9 years ago. It died on me within the first year, so i vowed never to get another Sony phone, even though i prefer just about everything else Sony makes, over other brands. Love my iPhone too much. I'm just waiting for the next model, which is supposedly going to be smaller than the 6 was. Hopefully it'll be back to about the size, that my iPhone 5 is.

I wonder if most people really care about the resolution of their phone's camera. I know I don't. I just imagine how much this will reflect on the price.

lol.. this is the real world.. it doesn't work that way.. that is like what i tell my students: "study hard, never give up, you'll eventually get a job.." some of them will never get a job in the field they are studying...  With the competition from, like everyone, Sony are in Mobile limbo.. Every company besides Apple and Samsung are struggeling with mobile..  if it was this easy to overcome the problems everyone would have already done it.. look at poor LG making almost 2 cent profit per phone.. 2 cents! 

http://www.mobileburn.com/24848/news/apple-dominates-money-league-few-android-companies-turn-profit

Still loving my Xperia Z1 and will definitely purchase another Xperia for my next phone, probably a compact version next.

Count me in, i've been keeping a close eye on the Xperia Z5 premium for quite some time now. Since it has been fully revealed, I hope the price is decent. I will be moving from my Galaxy Note 5 to an Xperia Z5 Premium, since originally having a Xperia Z1s. Those who say, "why do we need 4k in a smart phone?" Why not? What's so bad about having options, unless you don't like having options and just keep eating the same crap you've been fed forever. Blind consumers are hilarious.

4K is unnecessary for a phone but i understand that sony wants that feature to separate it from the rest when advertising it.