Actually, one-hand playing in this game is more easier. There are songs which can practice your one-hand ability.
Sta (also known as bit192) also contributed to Rayark's games, such as Cytus and Deemo.
In Press/Start, the Normal-leveled song is not Normal. Instead, it displays as "Level"
Levels are arranged from least to greatest, regardless of the mode.
Spherical songs are special songs. They are just like normal songs, but, they will appear in a specific time or day. Getting 2 stars or above on those songs will unlocked permanently.
Spin Angular Momentum does NOT have a level, because you can't achieve a full combo, and that is humanly impossible. Instead, it is placed in the last of the songlist.
Sta and Cranky have the most songs in this game, and one of their songs is also one of the hardest songs in Tone Sphere.