There are many ways to speed up your android system. Lets start….first tip is to remove widgets from your android home screen, of course, if you do not need it. If you have 2 or more widgets, try to disable one of them.
Second tip to speed up your android system is to disable Live Wallpaper if you want to smoothly scrolling through your desktops.
Third and most efficient way to speed it up is to close/kill applications that are currently not in use.
If you have more than 10 applications running at the same time, your system will probably be slow and it will probably spent your battery faster.
There are many good apps for closing/killing background running processes and applications on your android phone or tablet, but best one is Android App Killer which you can find in Android Market and install it for free (do not install unnecessary performance booster apps – it will only slow up your system, Android Task Killer is enough).
Also, you must check and update your system with latest updates for your android operating system. It will fix bugs on your current android version and speed it up. Note that only official updates will affect on this changes.
If all this tips do not help you to speed up your android OS, you will probably need to do Factory Reset of your android device (Note that Factory Reset will erase all your files and applications).
That is it, try to apply these tips on your Android Phone or Tablet PC and speed up your operating system and get some free RAM for faster and better system work.