For TikTok specifically on iOS farms, the trust signal stack is different from IG. You need SIM presence (not just eSIM), US carrier IP matching the SIM's region, and touch input patterns that vary across devices. TikTok's SDK reads device motion sensors during scroll - if 10 phones show identical accelerometer patterns, they cluster them. We stagger the warm-up schedules so each device has unique session timing. Also worth noting: TikTok checks for personal hotspot usage now, so cellular-only is safer than WiFi sharing across the farm.