Yesterday I made my first (what I consider) large Bitcoin purchase of ~$200 from a Bitnational ATM on my phone's Mycelium app.
At first the ATM was not working (just a black screen) but I waited around for 20min and it sorted itself out.
And than I used the BTC to purchase STEEM (from within steemit.com), was pretty exciting I gotta say.
Took about 15m for BTC to show on my wallet and about the same time for the BTC -> STEEM transaction.