MIUI (1.7.22) uses Arial as the default font. If you hate it as I do, here is how to change it.
I assume you have ‘adb’ working. We are going to replace only 2 fonts – Arial.ttf and Arial-Bold.ttf.
First, let’s back up the old fonts just in case thing didn’t go well as we want to. (I learned this the hard way, and keen to avoid it at all cost)
$ adb pull /system/fonts/Arial.ttf
$ adb pull /system/fonts/Arial-Bold.ttf
You should have a copy of the above 2 fonts on your local computer. Next is to connect to your phone and replace those fonts with DroidSans.ttf and DroidSans-Bold.ttf respectively.
$ adb shell
# cd /system/fonts
# cp DroidSans.ttf Arial.ttf
# cp DroidSans-Bold.ttf Arial-Bold.ttf
Restart your phone. Voila, your text doesn’t look as ugly as before; well at least that’s what I think.