The problem is everyone defends whichever platform they're using and gets defensive when someone accuses their beloved phone of lagging.
Never owned an S3 but given it's a couple generations old, it's likely no more
laggy by todays standards than my iPhone 4s is. If you've actually used an S5 or a Note 3 (which I own) when set up properly, there's zero lag.
Having used an S3 for 2 years I know for a fact Android lags, often in unpredictable ways. I've demoed the Note 3 and S5 in the store I can notice the lag in a 5 minute demo.
If you're basing your decision on a 5 minute in-store play sessoin with a phone that you're not familiar with, then you're selling yourself short.
While I would like the best of both platforms I'll take slower scrolling to get rid of those unpredictable laggy moments in Touchwiz.
The problem is you're running touchwiz. Not knocking it, I've just chosen to use Nova Launcher Pro which IMO is far better. On the S5 and Note 3, you can turn off all 3 animation settings for instant everything. You can also replace the dialer app.
All of the above are "options" that the phone was designed to have in the hands of the owner should the few milliseconds of animations and delays that are there out of the box both you. Most of which are not offered on the iPhone. Don't like their music EQ System, dialer or iMessage App then you're SOL.
And the first thing you should turn off in iOS is the transitions.
Again, that's the first thing you should do on Android too...IMO.
Then you hear about these magical tweaks...that don't fix the issue.
The options I mentioned 100% remove the objections you've mentioned.
The final thing is the mythical software update that...wait for it...doesn't fix the lag.
OS update? Again, see my updates and there's zero lag.
All signs point to Touchwiz being the culprit.
You know my car bogs and lags when I have traction control on during spirited driving too.
Pro Tip: turn it off
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Will this lag be fixed? Kind of annoying having to deal with an issue like this on a "premium" smartphone.
The lag being discussed isn't really "lag". Unless you're completely annoyed at any type of animation/transition. I equate what is being discussed to the same type of delay on many cable boxes. When I push channel up it "lags" but if I use the menu button scroll through the stations and click ok, it jumps to the station immediately.
I also think many of the issues are from people who constantly close their apps vs letting the OS manage them. I have hundreds of photos on my Note 3 and if I shut everything down and reboot then open the photo app it will take a brief second to begin loading the images. Not even lag, just a brief millisecond. However I never close my photo app as there's zero need. The phone will reassign RAM if and when needed thus no matter when I pull it up, that brief millisecond of "lag" is gone.
You don't stop your car and turn it off at red lights while driving do you? Of course not. Even hybrids control such things automatically. Then don't start and stop apps on a smartphone when you're using it throughout the day.