All the content included in MIUI Theme App is divided into several tabs. Use the first one to change the theme; you can choose between several options that'll give your smartphone a totally different look. The rest of the tabs can be used to change more specific aspects of the interface, the wallpaper, ringtones or the font.
Each tab includes perfectly organized content. By default, you'll always view the most popular content first, but you can always use the search box to find more specific content.
MIUI Theme App is an excellent customization app, but keep in mind that it only works with Xiaomi smartphones. It is also important to keep in mind that if you install the app, but you CAN'T find it anywhere, you just have to change your smartphone's region to India. This option can be found inside 'additional options'.