I'm looking to buy a new phone and I'm in need of an advice. I want something smaller and I have found a 4.6inch Android smartphone which is great for me (Sony Xperia XZ1 Compact). It is all around a good phone but it has a screen resolution of only 1280x720 pixels. For me that's perfectly okay, I even like it because that means better battery life since it has to render much less pixels. But what I'm afraid of is that app or web developers would stop supporting smaller resolutions like this one in near future and I would be left behind with my decent but low-res phone. Because of the low resolution I'm also considering a Sony Xperia XZ1 (not the Compact one) which has 1920x1080 screen resolution but it is a much bigger phone which I really don't like and would like to avoid (on the other hand it's much cheaper only 250 eur vs 350 eur for the Compact, but price is not the priority in this case).
And also this is my first Android smartphone (I have Lumia 820 and before that I had Lumia 800) so I don't know how it works in the Play Store with the support of so many different phones. (For example does the developer define a specific devices which are supported and anyone with a different device isn't able to install the app? Or is there a minimum supported resolution defined for each app and phones with a lower resolutions aren't able to install the app?)
Thank you for the answers.