With coinbase I have found it to be the easiest, you can convert any coin, on any system or app to LTC BTC or ETH and transfer over to Coinbase almost instantly it seems, then right into your bank account for a couple bucks. I like it this way personally.
I have seen and heard other ways to save a few dollars on transferring, etc but id rather have instant access.
I use Genesis mining for ETH, will jump into more when contracts open. Coinbase to hold ETH BT LTC and love it here on steemit to earn!