Memory Booster Ad-Free is no charge today on the Amazon Appstore, and I wouldn't jump to get this one folks.
You may hear a familiar tune with yet another task killer of sorts being thrown at an unsuspecting population of frugal Android app shoppers. If your devices is running Android OS 2.2 or higher then you do not need and should not download any task killers, let alone use them. The reason for this is simply that your operating system is designed to manage its own memory in a way that optimizes battery consumption while allowing apps to run tiny sized files in the background for various reasons. These background functions are commonly necessary for your phones day to day functions.
For example, most widgets are active widgets displaying some bits of information that may utilize the internet or GPS to show accurate info. A clock, the Facebook widget, etc. They require a small amount of your system RAM to function. If you were to kill all the apps running in the background to free up memory, these widgets would just start up again, and the process of stopping and starting can actually consume more battery than just running all day.
On a rare occasion an app may be behaving badly and is consuming an excess of system RAM and/or battery. You can manual kill that individual app using your built in system resources. For my Fascinate, I just long press the Home button to get the recently used apps pop up and hit the Task Manager button. There I have access to kill active apps, uninstall package files (apps), manage the RAM for killing background or inactive processes, and see and summary of everything running.
Now you must understand that your phones RAM is meant to used. While it is in your phone, having free RAM isn't necessarily a good thing. It doesn't make your phone running much faster if RAM is not being taxed, though if you are taxing it and you go to open a big heavy hitting RAM users like a PopCap game or other, then you may experience some unpleasantries due to a lack of memory. Though remember, Android 2.2 is smart about this and will find a way to give you the RAM you need to run what you choose to run.
Memory Booster is a fine app for what it worth. It is attractive and simple in design. This simplicity gets the best of it though as the app shows you ALL process running in the background, even the phone or OS specific programs that are required by the phone. Killing these apps can cause some serious headaches to your phone potentially ending you up in a place with a non-operational phone.
When you download this app I will automatically put itself into auto-task killing mode. It calls it Memory Boosting but we all know better. This app will run in the background killing the same apps all day long because they just keep reopening. In the end, don't download this app and don't get into the habit of killing apps.
Memory Booster Ad-Free -