Different agency, different statute, different minimum limits, different fees, and a different court system. Iowa filings go to the Iowa DOT under Iowa Code chapter 321A; Nebraska filings go to the DMV under chapter 60 of the Nebraska statutes.
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The practical differences worth knowing in this market are four. The filing agency is the Iowa Department of Transportation rather than a DMV, and its notices, forms, and fee schedule are its own. The criminal side runs through Iowa unified district court rather than Nebraska county courts, so a Pottawattamie County case is an Iowa District Court matter. Impaired driving is handled under Iowa Code chapter 321J rather than Nebraska statute, and Iowa administers its own temporary restricted license with an interlock requirement rather than Nebraska interlock permit. And minimum liability limits are set separately by each state, so a policy sized to one state floor is not automatically sized to the other. None of this is exotic; it just has to be handled from the correct state sources.