There's another important difference: Dash is marketed as a currency and STEEM as a social network. IMHO this is a huge opportunity being missed. But perhaps there are strategic reasons STEEM as currency is not being sold more aggressively right now.
In my opinion there can be any number of apps that can show strength of STEEM as a currency as well. For example, eSteem desktop soon will allow you to use it solely as a wallet....