[Xperia Play General] Miichaell:
Hi, I try to answer your questions, but it's not so easy.

Xperia Play have never got Android 4. The last official release is Gingerbred 2.3.4. On your S2 you was used to on ISC or higher I think. ICS fo Xplay was released only like beta (you can still download it on Sony's webpage). You have three options:

Android 2.3 which was official and with full support - it means gamepad, touchpads and everything else is working. It gets you the best performance, official PSX emulator works (you can convert your own games with PSXperia - not all games run through this emulator - e.g. Tony Hawk's titles, NHL's etc. not), but many games is compiled to higher Android versions or even many games lost support for Gingerbread in time (Trial 3, Trials Frontier, Crossy Road, Gangstar Vegas etc.)

Android 4.0 which was released only in beta - it has gamepad and touchpad support, but not in all games (however there is only few games with this problem). Performance is significantly worse (480p kernel is not an option, it's must have), official PSX emulator doesn't works there. But with RAM Manager/Boost my Xperia, smart swap settings and overclocking you can play almost everything (there are some lags here and there, but it's playable).

Android 4.1 which is minimum Android version if you want to use more and more "modern" material version of apps and some aps and games generally (Tomb Rider Go, new Nova Launcher, new Solid Explorer etc.). It has almost no support for touchpads but even gamepad - even with touchpad activator. Modern Combat 4, FIFA 12 and long list of games in 4.1 have no touchpad or even gamepad support (in MC4 for example gamepad works, touchpads not, FIFA 12 completely without Xplay support). You can always use GameKeyboard and map the buttons, but it's not so comfortable and offten even so optimized like the original solution from developer (FIFA12) - however sometimes it's vice versa and touchpad implementation from developer is horrible (Splinter Cell Conviction).

Of course, there are some projects with 4.2, 4.4 even 5.0, but it's not for daily use and totaly not for gaming.

There are some good ROMs for all three version:

Android 2.3 Gingerbread:

1) Gin2Kittkat 3.3.0 - in my opinion it's the most powerful ROM for Xperia Play - in terms of options and theming so as in pure performance

2) AuroraPlay - in 2013 it was the number one in pefrormance, but nowadays G2KK is better and newer

3) NXT ROMs - I have used them in 2012/2013 and they were awesome. Second version is beautifull :)

Android 4.0 IceCream Sandwich - most of them are Sony based, for example NexPlay is Cyanogenmod based (I don't know if it has touchpad support, but I think not)

1) Xperia Play Z Final Edition - I'm using it right now and with some of my modifications (debloated, replaced apks, removed small aps, changed bootanimation etc.) it is the best ROM for this phone in terms of modern system/gaming support. It has touchpad support in all games I've tried (I think ironic is that MC4 or Asphalt 8 run better than Crossy Road or Puzzle Craft 2), you can run some other aplications and games you cannot on GB.

2) Ultimate HD - it lacs some features which Play Z ROM have, but it's nothing important (at least for me). Only auto brightness doesn't work for me.

3) Express ICS

4) Neo2Play - aromainstaller with options what would you like to install

Android 4.1.2 Jelly Bean - all JB ROMs are based on Cyanogen mod cause official JB never comes to Xperia 2011 phones

1) Paranoid Android - best ROM for me if I have to choose JB. As the only one it has brightness slider in notification toggles area

2) Sonygenmod 10 - it looks like official Sony themed Android with ported Sony apps.

3) Slimbeam - it's fast and stable

4) JellyZeusbean - also Sony themed ROM

I think the best kernels are Lupus - for GB and JB. For ICS it's the same I think. But Lupus for ICS has small data partition, so rather use Lupus ICS/GB or Doom ICS (and Link2SD cause 600MB is still not enough). For GB there is also Extreme kernel, which has fantastic performance, but battery drain is crazy. If you want better performance choose 480p version which can offer more free RAM (even 30-50MB). I think there are better ways how to record videos than with Xperia Play. All of these kernels allow you to overclock, but remember - higher frequency meand shorter battery life. And for example my phone cannot go higher than 1,5GHz, on 1,6 it will restart itself. 1,4GHz is enough for everything, small performance is mainly cause weak GPU. Higher frequencies allow you max play some games in FPSe witch OpenGL on.

You cannot simply add or change RAM capacity. You can make swap partition on your SD card, download file with swap script, or you can simply use Swapper (it's not practical). This will free up some ROM, not add capacity. It's necessary for some games which need more RAM than you physicaly have (I remember Angry Birds Go was impossible to run without swap partition). Here is the topic. Best setting for swap is 20 (on all versions of Android) in my opinion. In ICS and JB you can try 40 or even 60, but my experience is long response time and worse performance at all.

Some other tips: delete facebook and Messenger - they are killing performance and response time. Use Facebook lite or web browser. Don't install any apps you don't need or you aren't using more than 1 per month. More apps means more Link2SD apps and they are slowing down the phone. On Gingerbread use Nemus Launcher (till 2012 not in GPlay) or Xperia T modded launcher (the fastest) if you don't need features which has Nemus. On ICS or JB you can use Xperia Z modded launcher, Nemus or Nova (I'm using it right now and it's very good, fluid and if you run some game, it goes off the RAM). On GB you can also flash Adreno Booster, in some games you achieve better performance, in orhers more stable FPS.