So what are people downloading?

Downloading unofficial "Mobile" versions of Nintendo games poses significant risks: Security Threats

: Users often report being redirected to unrelated games or ad-heavy websites instead of a real game. Legitimate Ways to Play on Mobile

by Nintendo. These may contain malware or be simplified "lite" versions that lack core features like Course World online sharing.

Early emulated versions (2.0.x) suffered from frame drops, audio glitches, and crashes when too many enemies were on screen. The 3.0.0 "BETTER" repacks include (for Snapdragon 865/888/8 Gen 1/8 Gen 2 processors) that lock the game at 50-60 FPS on high-end Android devices. On iOS (via sideloading/AltStore), performance is even smoother.