What if you have a first-world problem and your cell service is too good and reliable - even forcing the phone to 2G/3G service is not simulation enough.
the you spend some time defining what a typical 2G and 3G connection looks like to your end users, and then you replicate that with existing tools. There are very, very many open source solutions to adding latency, jitter, throttling bandwidth, and replicating packet loss. in fact, I'd argue that coming up with a few solid definitions of what a 2G and 3G connection look like is far more accurate than running tests over one dongle "IRL"
