I have 3.5 half year old Samsung / Google Galaxy Nexus i9250. The phone has become so slow after that time, that it is simply being unusable. Launching any application, as simple as Gmail or Calendar takes 2-3 seconds, sometimes even five. Pressing
Home button needs 4-5 seconds between press and really showing up main screen of my launcher (Nova Prime).
When I purchased this phone, it was simply lightning fast.
I have about 50 applications installed, of which about half is used (15 from time to time and 10 daily) and the other half, never used or used once per 2-3 months. Because I change my attitude very rarely, I have installed these applications in 2012, when I purchased my phone and haven't installed anything or nearly anything ever since that. I would describe this as changing 1-2 application per year.
Because of above, I can hardly accept, that my phone is slow, because I installed too many applications during that 3.5 year period. We can assume, that I'm sitting on the same apps set for past 1-2 years. It is also hard for me to belive, that 50 apps, of which half is nearly never used is enough to visually reduce performance of such phone. Even though it is quite old, its hardware isn't that weak, as I assume.
I of course did a full factory reset once or twice, installing only the same set of applications, as in 2012, after that. It brought little or no help and little or no performance gain. This has actually "killed" me, because I was more than sure, that full factory reset will return this phone to a level of performance and speed close to the days, as it was brand new.
The only theory, that comes to my mind -- though very strange and unbelievable -- is that my battery is old, its performance is far lower than when it was brand new, and thus it powers all hardware with lesser voltage causing its overall performance to degrade.
I know, how stupidly this theory sounds, but it is the only one, I managed to come with, in given situation.
Assuming that number of installed applications and overall usage style of my phone hasn't changed over past 3.5 years of using it, is there any reasonable reason for why it is so extremely slower than it was, when it was brand new?