Sprint is apparently going to fall in line with Verizon and AT&T in raising its Early Termination Fee on "Advanced Devices." On September 9th, it appears that Sprint will raise the ETF to $350, which matches what Verizon charges and is slightly higher than AT&T's $325 fee. The change would leave T-Mobile as the only major US carrier with a smartphone ETF of $200. As with all carriers, Sprint's new charge will be pro-rated as your two-year contract winds down. PhoneNews seems to have a statement from Sprint that puts the finger on the increased cost of smartphones as the root cause. SprintFeed also has an internal screenshot confirming that the change is coming. So if you're thinking of picking up a Samsung Galaxy S II Epic 4G Touch on September 16th, don't say we didn't warn you.