Explained
A mobile proxy uses an IP address assigned by a mobile carrier (Verizon, T-Mobile, AT&T, EE, Vodafone, etc.) to a real mobile device on a 3G, 4G, or 5G network. The IP looks like a normal cellphone connecting to the internet — because it is.
What makes mobile proxies particularly hard to detect is CGNAT (Carrier-Grade NAT). Mobile carriers don't have enough public IPv4 addresses to give each device its own; instead, hundreds or thousands of subscribers share each public mobile IP through carrier-side NAT. From an anti-bot system's perspective, blocking a single mobile IP would block thousands of legitimate users on that carrier — so the major anti-bot vendors are extremely conservative about flagging mobile traffic.
This trust profile makes mobile proxies attractive for the most sensitive workflows. Shifter doesn't sell mobile proxies — we focus on residential and ISP (static residential) proxies, which cover the vast majority of scraping, ad-verification, and brand-protection workloads at a much better cost / performance trade-off. For the niche cases where mobile-grade trust is required, residential proxies paired with mobile User-Agents and realistic mobile session behavior gets most teams where they need to go.
How It Works
Mobile proxy providers obtain IPs by partnering with mobile carriers or by operating fleets of physical mobile devices (real phones with carrier SIMs) connected to the proxy gateway. When you send a request through a mobile proxy, your traffic is forwarded to a real mobile device or carrier endpoint, which sends the request out over its 4G/5G connection. The destination site sees a normal mobile carrier IP and treats the request as legitimate cellphone traffic.
Mobile IPs naturally rotate as the carrier reassigns them across the CGNAT pool — meaning even a 'static' mobile proxy can change IPs from the destination's perspective every few minutes or hours, which makes long-term tracking nearly impossible.