I have been waiting for a decent multi coin wallet that utilises arbitrage to cut costs.
e.g. You want to buy BTC, the app notices that you could get this cheapest (including fees) if you buy dash through website x, trade it for eth on exchange y then trade for btc on exchange z.
You just have to have accounts on all those exchanges or do an api deal or something to make it work.
Too complicated, right?

This idea would be perfectly suit to combine it with mine.