This guide  provides a number of tips you can use to speed up your phone, and while  not every tip will apply to you or your phone, you should find at least a  few tips in here that will. Whether you've rooted your phone,  overclocked, flashed a new ROM, or none of the above, you'll be able to  take advantage of a number of the tweaks below to get your phone from  sluggish and glitchy to quick and smooth.
Everyone's  phone is different, too, so note that some of the more advanced tweaks  may take a bit of trial and error on your part. I've experienced good  things with these tweaks on my Motorola Droid (which, yes, had gotten  pretty darn sluggish and glitchy, even for a barely year-old phone), but  I'll note where a different approach to a specific tweak will help  owners of older or more underpowered phones. Users with newer phones  (like the Droid Incredible or Galaxy S) may not need these tips as much,  but I've heard from several sources that even speedy phones like those  have benefited from these tips, so they're worth playing around with no  matter what phone you have.
If You Haven't Rooted Your Phone
There are a  lot of great tweaks out there for rooted phones, but there are a ton of  really simple things you can do to speed up your phone, even if you  haven't done any hacking whatsoever.
Try a New Home Screen Launcher
We've talked about the benefits of other home screen launchers on more than one occasion, but I can't stress how great of an upgrade this can be. As always, I'm a huge proponent of LauncherPro,  as it will not only bring you a noticeable speed increase upon  installing it, but it also has lots of advanced features we can tweak to  boost our speed even further (more on that later). Of course, ADWLauncher is also very popular, and the Android Market is rife with other options.I'm going  to write the rest of this tutorial from the perspective of a LauncherPro  user, since from what I've seen, it has the most speed-boosting  options, but you should be able to find many of the settings I mention  below in other launchers, too—I'll note where a few of them are along  the way, but you may have to do some poking around of your own depending  on what Launcher you're using.
Lower the Number of Home Screens You Use And Ditch Those Widgets
If you have  an HTC phone with the exclusive Sense UI and you'd rather not ditch it  for something like LauncherPro, that's fine—you can still put this tip  into practice. While some phones, like the Motorola Droid, come with a  mere three five home screens, many (including most HTC phones)  come with up to seven. While this is pretty handy if you like lots of  icons and widgets (which I'll mention again in a moment), they can  really take up a lot of memory on your phone, which can cause jerky  animations, lag, and force closes.
In our guide to organizing your Android home screen,  we mentioned the two philosophies behind home screen usage. It's fine  to have lots of home screens, icons, and widgets, but if your phone  isn't performing up to your standards, you may have to compromise and  try using fewer home screens (or at least find a middle ground). I went  down from seven to three home screens and haven't looked back—the jump  in performance was pretty incredible.
If you're  using LauncherPro, you can pick your number of home screens by hitting  the Menu button on your phone, tapping Preferences, then tapping  Homescreen Settings. If you're sticking with your stock launcher, you  may not have the option to actually decrease the number of home screens,  but you can still benefit by removing some icons and widgets from two  to four of your home screens. It probably won't give you as big  of a benefit as getting rid of the screens entirely, but those widgets  can still suck up tons of memory, and deleting them from your home  screen should make your phone run noticeably smoother.
Uninstall Misbehaving Apps
When we discussed the myth of Android task killers,  we mentioned that one of the real problems with slow phones is running  poorly coded apps—apps that use up too much CPU in the background. Previously mentioned Watchdog is still a great way to keep track of those apps: if something is  constantly running in the background, it may be causing some of the  performance hits on your device. Unless it's something you can't live  without (and are thus willing to live with any slowness it might cause),  uninstall it and find an alternative.
Uninstall or Move Apps to Free Up Space
It's also  worth mentioning that even if an app doesn't misbehave (heck, even if  you don't run it at all), it can cause slowdowns on your device. Believe it or not,  the more free space you have in your phone's internal memory, the  faster your phone can write to the disk. If you aren't sure how much  free space your phone has, you can check it by going to Settings > SD  Card & Phone Storage to see. You can also see which ones are taking  up the most space by going to Settings > Applications > Manage  Applications, hitting Menu, and sorting them by size. If you find you  aren't even using an app that's hogging space, you might as well  uninstall it—no point in keeping it around just so it can slow down your  phone.
Your other  option is to use the ever-handy Apps2Sd to move some of those apps off  your phone's internal storage and onto your SD card. By default, the  developer of a given app usually decides whether an app will install to  your SD card, but with the App 2 SD app, you can do it yourself. Just pop open the app, and you'll get a  list of apps that are on your internal storage that have the ability to  move to the SD card. Just move them over to free up space. 
Tweak Your Launcher's Memory Usage
If you  really want to dig into your system's settings (or you compromised on  that "use fewer home screens" tip), there are a few more advanced tweaks  you can make to your launcher that should help it run a bit smoother.
If you're  using LauncherPro, hit the Menu button and go to Preferences >  Advanced Settings > Memory Usage Settings. While you can tweak the  Advanced Settings to your liking, the easiest way to take advantage it  to use one of LauncherPro's many Memory Usage Presets. These presets  tweak different settings to fit the needs for different people and  different phones. You can read more about these settings on the LauncherPro blog, but here's what you really need to know: Starting  with version 0.6.1, there is a new option in the preferences called  "Memory usage". Right now there are three modes; light, medium, and  high.
- Light  mode is basically what 0.6.0 uses, and it's made for users that have 5  or more screens, a lot of widgets/icons (or many full-screen widgets),  3D drawer, etc.
- Medium is the default, it should work best for most users with a moderate-to-high amount of widgets/icons.
- High  mode doesn't try to optimize memory usage. It's very much like the  early versions of LauncherPro, so it should give the best performance.  If you don't have a lot of widgets/icons on your screens, you should try  this setting.
Note that  there are now more than three presets, but the general premise remains  the same. If you're still filling up your home screen with icons and  widgets, you might want to try out a setting on the low end of the list.  If you've taken my advice thus far, I can tell you High mode will give  you a pretty nice performance boost.
One great  thing about LauncherPro is that if you go to Preferences > Advanced  Settings and check Display Memory Usages, you'll be able to see how much  RAM is being used at any given time. This is a good way to tell whether  you have RAM to allocate to these different things, or whether the  amount of RAM is too small to let LauncherPro keep trying to use it all  up.
If you're  using ADWLauncher, you won't have nearly as many choices, but I would  still recommend going into ADW's settings, hitting System Preferences,  and playing around with a few of the features there like Scrolling cache  and System persistent, which should perform similar tasks (albeit not  as well as LauncherPro or CyanogenMod's similar settings, which I'll  talk about in the section for rooted phones).
If You've Rooted Your Phone
If you've taken the plunge and rooted your Android device,  you have a few more options available to you that should help you eke  some extra speed out of your device. Note that these are a bit more  advanced (as would be expected with root-only options), and require a  bit more care, so be sure to backup your phone before you make any huge  changes to it in case anything goes wrong.
Still  one of the best reasons to root your phone is to install a custom ROM,  not only for the neat features it brings but for the speed increases it  can bring your phone. We've gone through the details of installing custom ROMs before,  so I won't go too deeply into it here, but I do recommend it if you  need some speed increases, especially if the ROM is based off a later  version of Android than your phone currently has. Lots of phones are  still stuck with 2.1 and earlier, and while some ROMs can run a bit  slower than stock Android on some phones, the speed increases Android  2.2 brings likely outweigh them.
Many ROMs  are built for speed and stability, and while you'll get a great  performance boost from them, I've found that even with a ROM like  CyanogenMod I've been able to eke some good performance out of my phone  (especially by tweaking some of CyanogenMod's advanced features). So  don't think that you have to choose a ROM like Bugless Beast just  because you have an old phone. Of course, trying a few different ROMs is  always a good idea to see what works best for you.
Overclock Your Phone's Processor

A surefire way to get a speed boost out of your old, underpowered phone is to overclock it. We've also discussed this already before, so we won't get too deep into it here, but I will remind you that to overclock, you'll need to install a custom kernel.  These are specific to your device, so you'll have to do some googling  for compatible overclocking kernels to find one that's right for you.  Generally, kernels are organized by two things: voltage and clock speed.  The higher clock speed you choose, the more likely you'll need a higher  voltage kernel (which, by the way, will drain battery faster). As long  as you're not going overboard with the overclocking, you should be able  to get by with a low or standard voltage kernel without a problem.Uninstall Crapware
If your phone came pre-installed with all sorts of applications that you don't need, you can unisntall them with an app called Titanium Backup.  Once you've downloaded it, just open it up and hit the "Backup/Restore"  button at the top of the screen. Tap the app you want to get rid of.  You'll probably want to back it up first, in case it ends up being  integral to your phone's operation, but once you have you can uninstall  it from the same screen. Alternatively, you can just freeze the app,  which won't free up space on your phone's memory, but will keep it from  running in the background and slowing your phone down. Note also that,  like all these root-only options, you could seriously mess up your phone  if you go too crazy, so maybe a full-phone backup is also a good choice  here.
Play With Your ROM's Advanced Settings
This is one  of the most difficult tweaks to perform on your phone, because it  varies so much from person to person what works best. Furthermore, some  ROMs may not have these settings in their preferences—you may have to do  some terminal work to enable them. I'll go through what they are, and  point out their location in the CyanogenMod ROM since it's the most  popular and widely available, but if you don't have them in your ROMs  settings you may have to do some googling to find out how to tweak them.  That said, here are some of the handier features.
Compcache:  Compcache is essentially virtual swap space in your RAM. In a nutshell,  it gives you "more" RAM, but it's a bit slower than regular RAM because  it takes CPU to compress and decompress packages that are swapped into  it. This is one of the most debated features: many find that it helps  things like the home screen load faster; others prefer to keep it off.  Try it both ways and see what works for you. New versions of CyanogenMod  also allow you to choose how much RAM compcache sets aside as virtual  swap space, so you can play around with that as you so choose.
JIT:  JIT is a Java compiler available in Android 2.2. Enabling it won't give  you a big speed increase as far as small apps, loading the home screen,  and other such niceties, but it will likely give you a big speed boost  in intense applications, like games.
Lock Home in Memory:  This is similar to the LauncherPro memory features we discussed above,  as it attempts to do exactly what its name implies: keep your home  screens in memory so that it doesn't have to keep redrawing them all the  time. I'd recommend enabling this if you have the memory for it.
VM Heap Size:  This is one of the more interesting settings. the VM heap size is the  maximum amount of memory an application is allowed to allocate.  Resource-intensive apps will require a larger VM heap, while simper apps  don't need as much. You'll want to play around with this setting, but  you should be able to tell after going through the other settings what  setting you'll want here. If you allocating tons of memory to  LauncherPro, or your have JIT enabled for resource-intensive  applications, you might want to try 32M. If you're trying a more  minimalistic approach to everything, you might find 16M or even 12M  boosts the speed of your phone considerably.
With all  these settings, try changing just one at a time and see how your phone  responds over the course of a day or two. Everyone's settings will be  different; there is no one size fits all here. Depending on your phone,  the apps you use, how you've set up your home screens, and other tweaks  you've made, your phone will respond differently to different settings.  So, if you're dedicated to messing around with them, go for  it—otherwise, you'll probably just want to leave them at their defaults  (which are set on a per-model basis, for what it's worth). Also note  that if you start messing with these settings, you never know what might  happen, so many developers won't let you submit bug reports if you've  changed the defaults. And, of course, always always always make a  backup.