Hah, if you wanna skew the elections, there are much more subtle ways to do this. For example, to find data manipulation in Russian election you need to use statistic methods (there are plenty of articles about it, mostly in Russian though). When you control the counting process, especially electronic (that it fully black box for outsider), you may change numbers silently.
Americans are straightforward people, but changing "wrong" results by app crash is too much even for them. Especially when everyone expect that this will happen, it is too obvious.
Maybe democrats trying to use same strategy as Trump in past - betting on "anti-establishment candidate". Look, the evil corporate guys already bully our people's candidate, please vote for him to make establishment suffer. Please mobilize asap, because they already trying to steal his votes, but WE THE PEOPLE can protect our democracy. Big evil business (also not environmental friendly) HATE Bernie very much - it is written in every (corporate) media outlet now.
Although another reasonable explanation is simple mismanagement. Knowing how software development works, it is pretty realistic. That poor Indian who did all work isn't superman to do everything good, especially when he received only few dollars at the end of outsourcing chain.