http://www.lockergnome.com/android/2011/12/26/should-you-install-a-custom-rom-on-your-android-device/ i found this information there for anypne eho is wondering Are YOU one of those people wondering what a rom is? a rom is like an operating system its called a ROM because it installes to the ROM chip on your phones motherboard now to the pros and cons of it all ___________________________________________________________________ Reasons you should not install a custom ROM: -You will void your warranty. The manufacturer or third-party warranty company will not be willing to repair a damaged phone that has been rooted or has a custom ROM installed. While the ROM may not be the cause of the issue, your warranty will still be voided. -During the process of rooting, something may go wrong. You could brick your phone. There are ways to unbrick it, but you could potentially need a new phone. Without your warranty (you just voided it), you will have to pay full retail price for a replacement. -Custom ROMs may cause you to experience odd issues. I once used a ROM that would crash every two to three minutes during phone calls. It was extremely frustrating. -Custom ROMs update quite frequently to fix bugs. (Sometimes causing more bugs, but that’s another story.) You’ll end up having to update every few days, sometimes even having to wipe your data and restore it later. This can be a good thing, because bugs are getting fixed, but it can also be annoying to have to update that frequently. -You may accidentally give a malicious app root access, allowing the app to do whatever it wants to do with your phone. It could potentially wipe all of your data, take your files, including private pictures, and send spam to your contacts. why you want it Reasons you should install a custom ROM: -Kernels: Custom ROMs usually also come with a custom kernel, which gives you many advantages over the stock kernel. For example, ROMs using BobZhome's custom kernel built for IHO can use the cifs module he built with it. This allows you to access your PC via Samba/CIFs file systems using an app called cifs manager. The difference between this and most file browsing methods is that you can use the file as if it were on your phone. So for example, a video file will start to stream from your PC instead of having to transfer over to your phone before playing, and a PDF file will open immediately instead of transferring. -Tethering. While this does void your carrier’s terms of service, and I do not recommend doing it without a tethering plan, custom ROMs usually provide you with the ability to tether without a tethering plan. It is often the only reason people want to install a custom ROM. Again, I do not recommend this because you may eventually be caught and your service may be terminated. It is essentially stealing from your carrier. You’d be getting one of its services for free. -Battery life improvements. With root access, you have the ability to calibrate your battery, which usually will fix any issues you’re having with battery life. Some custom ROMs also under clock the CPU to reduce battery usage. With my ROM, I get a few more hours of battery life than I had with the stock ROM, and performance is actually better. If battery life improvement is all you’re interested in, I recommend that you try JuiceDefender. It’s an app that manages your wireless connections and disables them when your phone is locked to save battery life. It enables the connections once every 15 minutes so that you can still get notifications. -Apps. Some apps require root access. A good example of this is DroidWall, which lets you keep apps from using data while on 3G. This is great if you’re on a limited data plan and getting close to your limit. I’m also a fan of BatteryCalibrator, which is the app I use to calibrate my battery after flashing a new ROM. -Over clocking and under clocking. You can use an app, such as SetCPU, to over clock your phone, giving it better performance, but sacrificing battery life. This may be something you want to do if you’re having trouble running a game you really want to play. Some Custom ROMs are already configured to over clock your phone. You may also be interested in under clocking your phone. Under clocking reduces performance but increases battery life. -Newer Android versions. I’m excited to try Ice Cream Sandwich, but a release date for this update, for my phone, has not been announced yet. I believe that there are more reasons to install a custom ROM than to stick with the stock ROM, but I still don’t recommend it for everyone. You must be willing to deal with getting it set up, backing up all of your apps, restoring them after flashing, calibrating your battery, and updating very frequently.