Gerrymandering would only change a state’s electoral college votes meaningfully in one or two states.
It’s more often an issue of:
- Citizen becomes voter via “motor-votor” registration.
- Later, state sends postcard asking to confirm voter’s address.
- Voter sees postcard, looks like junkmail or fraudulent mail, discards without response.
- State, not checking anything else, drops voter from roll.
I was going to mention that if you’re out and about, StreetComplete and Every Door and MapComplete are excellent for gamifying casual contributions. OsmAnd has savable custom searches.
But if you’re wanting to compare, I’m gussing you might be wanting more than opening hours and cuisine, perhaps reviews?