It's easy to take fonts for granted, but a huge amount of effort goes into crafting them just-so. A well-designed font is just as readable large as it is small, and the eye should effortlessly be able to distinguish between characters. Maybe that's part of what keeps us from appreciating them — that a font that's doing its job well is one you won't have to pay attention to at all. Rather than let it become an unsung hero, Google's made a point to draw attention to the Roboto font it will be introducing in Ice Cream Sandwich. If you don't want to wait until your phone's running Android 4.0 to check out Roboto, the font is available for download now.
It's a little trickier than getting one of the Ice Cream Sandwich wallpapers on your phone, but with a bit of effort you can install Roboto as the default Android font. Obviously, first you'll need the font files, downloadable over at the XDA-Developers forums. The easiest way to then set it as the system-wide font is with an app dedicated to such tasks. One that will work is Font Changer, but be aware that you'll need root access for it to make the needed changes. If you're using that app, you'll need to copy the Roboto files over to its folder on your SD card. Then simply run Font Changer, change the system font, and once your phone reboots you should (hopefully) be enjoying Roboto.
Via: Android Police