Default Arial font UIlabel can not display on some Android device

[asueliu]

Most of my testing device display my UIlabel ( which uses system font ) correctly.
But a few android device can not display any word( but only some punctuation marks ),even though my device system use same language as the UIlabel text.
Those device are Samsung SC-04F,LG L-01E.System language is Japanese.
Could any one please give me some advice to solve this ? Thanks.

[ArenMook]

You need to have the actual TTF in the assets folder, or have a bitmap font. Don't rely on the built-in font. It may or may not be there at Unity's whim.