This reminds me...
... of Tom Scott's excellent Computerphile video "Why electronic voting is a bad idea."
Sure,a caucus isn't a traditional vote, and the app was designed to work very differently from conventional voting software (it sounds like a variation-on-a-theme of a database form), but the same basic issues (especially transparency) remain.
Of course, the US is the one country where almost all conventional voting is carried out using closed source electronic voting machines rather than the antiquated but far more secure pencil and paper with single sealed black box per polling station (pencil to mitigate against the possibility of pens being filled with disappearing ink)...
Biting the hand that feeds IT
