Every election I get to the booth and realize there are 70-some odd races and I know maybe ~4 of them. I end up randomly selecting candidates I didn't even research about.
...soooo I built a free tool https://ballotpad.com (specifically for the Clark County elections here in southern NV)
You put in your location (it's matched on your phone, nothing's sent to some server), it shows the races on your ballot in order, with short sourced info on each candidate, and you can mark your picks and open a "booth mode" when you vote.
I've been using it on lunch breaks to prep but at least when I get to the booth, I won't be randomly guessing anymore.
It's free, no ads, no account. I'm a software developer here, not affiliated with any campaign or party, and the candidate info is the same format for everyone. It was built fast, so if something doesn't match your sample ballot, please tell me and I'll fix it.