Raven Coin transactions

To make this as short as possible –

I have been using the raven coin wallet app on my iphone. I recently decided I would start moving 100RVN for every 200 that I mine in to something that I can earn from (for example APY from coinbase)

what would be my most cost efficient way of doing this, currently I am just sending to Bittrex, then withdrawing to the destination after converting, but I assume somebody will know a better way to do this?

any help or advice is appreciated.