If you are currently deciding whether or not to jailbreak your phone, then let me put your indecisiveness to rest. The answer is simple: you should. There are no downsides to jail breaking your iPhone, it’s not illegal as many people think (it’s your phone so it’s up to you what you do with it) and it won’t cause any permanent damage even if you get it wrong as it’s completely reversible. There are plenty of places that can do it for you if you don’t feel confident and the amount of things you will be able to do once you’ve gone through the process that you couldn’t before is simply jaw-dropping. Jail breaking your phone basically means opening up the software so that you can download apps that edit all the files on the system. This then means that you can make changes to the way that the actual iOS works and can generally personalize your system to your heart’s content. Here we will look at some of the kinds of things you can do, but this is far from an exhaustive list.Emulators Emulators are basically programs that allow a machine to mimic another machine. In other words it means that you can run software that was meant originally for another device. The main purpose of this is normally for gaming, and there are many different emulators designed to mimic machines like the Sega Genesis and the SNES. Now the good news is that you can do this completely for free and completely legally. That’s because you’re allowed to play the games if you have them already in their original cartridge form which means that you can start playing Sonic the Hedgehog or Mario on your phone.Something I personally find even more interesting about this though is the large indie scene that revolves around transforming those classic games into new versions. There are countess Sonic games for instance that have been made by fans that give Sonic new moves and change the level layouts and sprites. It’s like having brand new games on your phone and it’s a lot of fun.Another interesting use for emulators is emulating old PCs. There’s a ZX Spectrum emulator out there which is great for a bit of nostalgia, but actually useful is the Dos emulator that allows you to play old Dos games and files. I use it to run Word 5.5 which is available completely for free and legally and which has lots of the features you’d associate with a modern word processor ñ you can even tile multiple windows. If you have fond memories of QBasic like me (hello there fellow nerd!) then you can get that up and running too.CustomizationOne big downside of iPhones is that they all look pretty much much of a muchness (how many much’s can you get into one sentence??). They aren’t customizable or very individual and other than a bit of wallpaper they all look the same. Well this is no longer the case with a jailbroken iPhone which will allow you to change the backgrounds, but also the skins on all of your dialogue boxes, message boxes, buttons, windows and just about everything else. You can even change the number of icons on your dock so that you can launch more things at your convenience. Very handy.Even more useful though is the ability to change your browser AND your keyboard (finally) so if you don’t want to be stuck with the stock software here anymore then now’s your chance to break free like Freddie Mercury.Robbie Crowe has shared some amazing tips for jailbreaking and having the best apps in your†iPhone. You can download iPhone 4 jailbreak software from his website.