A residential proxy sends traffic through IP addresses assigned to home internet connections, so it looks like a regular household user. It is more trusted than a datacenter proxy, but quality varies, many are shared or recycled, and platforms increasingly flag known proxy ranges.
For mobile-first platforms, a mobile carrier IP is the gold standard — it is what real phones use. And a proxy still only changes the network; it does nothing about the device behind it.
DistrictDroid skips proxies entirely: each phone is a real device on a real US carrier SIM, so the connection is a genuine mobile IP and the device is genuine too — nothing layered, nothing shared.