Mobile phone carriers in the Philippines are Globe, SMART, SUN CELLULAR.
In Japan it is docomo, au, Softbank. Previously, the biggest docomo was considered to be the most influential in the range of support and voice quality. But now such differences are no longer being talked about.
In recent years, a business style called MVNO has become popular. They borrow communication lines from the three companies and offer their own services. Although we can not expect as much service as major carrier, we can use it cheaply.