This app was mentioned in 1 comment, with an average of 1.00 upvote
Saw that no one ended up creating an iOS version of a Sanders app so here is one that that was recently submitted to the app store: https://itunes.apple.com/us/app/sanders-2016/id1022730586?ls=1&mt=8
Has a newsfeed, his stance on issues, a link to his donate page, volunteer contact form and a UGC component. There's also an Android version of the same app: https://play.google.com/store/apps/details?id=com.get2016.sanders