Shiyin Box

Shiyin Box — a pocket audio library for kindergarten teachers. Turn a screen recording into an MP3: record with the mic off, come back, extract it in one tap, and copy it to your classroom speaker. Audio from WeChat works too — save it to Files, import it, and it becomes an MP3, filed by class and ready whenever you need it. • Extract from screen recordings: pick a video from Photos, get an MP3 • Import and convert: audio from WeChat, QQ, or email — import and convert • Organize by class: songs are auto-tagged by class, then preview, rename, or export to your speaker • Smart silence trim: cuts the dead air from the start of a recording Fully offline: all audio and settings stay on your phone. Nothing is collected or uploaded. Note: this app does not crack encrypted music formats (such as .ncm or .qmc), and WeChat voice messages (.silk) can't be converted directly — use a screen recording instead.