2/4 (二拍子) is the workhorse time signature of Chinese traditional music — guzheng, dizi, pipa, erhu, yangqin repertoire, beginner pieces and graded exam pieces alike. Unlike Western 4/4 it does not feel "square"; it pulses in a hard "strong-weak" two-beat pattern, very tight, very crisp.
This page is set to 90 BPM, 2/4, traditional drum — clear downbeat on beat 1, lighter on beat 2. That pattern matches the "板眼" (ban-yan) rhythmic structure of many traditional pieces, where 板 is the heavy beat and 眼 is the light one.
For more idiomatic regional styles (Jiangnan silk-and-bamboo, Cantonese music), you will also encounter 1/4, 3/8, and ornamental variations. The disciplined approach is to make sure your 板 always lands exactly on the downbeat. That is what traditional drum mode gives you, and what uniform mode would hide.
The app pre-sets to 90 BPM, 2/4, traditional mode. To adjust, use the controls inside the app after it loads.