Let me see . . . there seems to be a disagreement about the use of paper ballots versus electronic methods, some of which might offer access with cell-phones, tablets, lap-tops etc.
Now, think about this. We could study the design of ballots in various states, but I only have my firsthand experience in California. Some years ago, everyone in our family chose to use the "absentee ballot" method so they could get their ballot in the mail and return it by mail.
What advantage is there over a paper mail-in ballot and electronic ballots, if someone has to go to a polling place to use an electronic device? That's the first question.
And what is the difference in completing at home a paper ballot to mail in, as opposed to checking boxes or radio buttons from a mobile device? If you receive a paper ballot in the mail, you could take it with you to places where you'd want to have a cell-phone, and you could mail the completed ballot at that location.
In CA, the paper ballots simply require one to draw a line between the tail and head of an arrow pointing at the selected candidate. So you just draw some lines. Would you really want to fiddle with an online data entry screen with a mobile device? To do what? Select checkboxes or radio buttons?
The only chain of custody issue for a mail-in ballot involves the USPS. The USPS delivers and picks up mail in some 161,000 voting precincts. Who's going to infiltrate the USPS with any ability to intercept ballots? Unlikely. And contrary to the psychotic fantasies of GOP ideologues, the USPS is a reliable and fantastic institution, despite GOP efforts to emasculate it.