[Asus  Eee Pad Transformer Prime] pileot:
reguarding open apps

At times i noticed my stock launcher was laggy to switch between screens. After swiping to close the recent apps it was a lot more responsive, so i think that swiping the apps from the recent list does close them, at least in mose cases.

As to optimization apps, usually they are intended for phones running older software. You need to remember that every phone (aside from the google phones) is running a slightly different version of android.

Since each version of android is different, even between the Froyo on my phone and your phone, because they have different modifications on them there is a chance that the customized software on my phone may be better at handling unused tasks than your phone (in fact HTC phones by default have a LOT of running processes in the background, whereas Samsung phones generally have fewer).

A lot of these optimization apps do several things:

Turn off wifi and bluetooth when not needed

Close tasks when they are unused

lower screen brightness

turn off 3g and use 2g if available and not in a call

Now this may be excellent for your phone, it spends most of its time in your pocket, soon as you unlock it it can connect to wifi again, turn on bluetooth, etc.

HOWEVER!

If you have, say, the weather widget, or a clock, or in my case battery monitor pro, and the task killer is killing those tasks those widgets will no longer update.

Some tasks, like Maps, tend to start up automatically, meaning your wasting MORE battery life closing this app and then it restarts and you have to close it again. It takes less battery life having it run in the background.

Sometimes an app will close (like the browser) that your not fully done using. Theres a difference between the app being frozen in memory and fully closed. Both do not require much power, however when you open that process again the frozen one takes a LOT less battery than the unfrozen one.

On a tablet, having a case that has a magnet in the apropriate spot and, say, tasker (very good app for custimizing your own triggers to turn things on and off) to detect that sensor and shut off wifi, gps, bluetooth, etc. would be very cool. Many apps use the proximity sensor to detect if its in a pocket and shut off everything, or the lockscreen. Because the way a tablet is used many of these battery saver apps will actually use more battery than what would be used in the first place.

You also have to remember that as android advances there are more tweaks for battery life put into them. For instance, you can have ICS close tasks that are not being used right away to save memory and its pretty good about freezing things in background memory.

Older versions of android lacked these features, or they were poorly implimented. I remember on my vibrant i was always going back to make sure all my tasks were closed properly when i was done with them. With newer devices its not an issue android takes care of that for me.

TLDR: Try as many battery saver apps as you like, just be warey as to what devices they are designed for and what version of android they were made for. Doesnt mean they wont work, just means they may do something thats useless for using on a tablet.