Ok, after a little investigation because of the "crazy fees" post... I discovered that the Credit Card purchase in-app option that links to the Simplex service is a MASSIVE rip off.
Currently (1000 hrs UTC 2017-02-17), this service is charging USD$1200 for 1 BTC. The going rate is around USD$1050 for 1 BTC. That is a markup of around 15%!!?!
The poor guy in the crazy fees thread paid $50 and got $36 worth of bitcoins... which is a 30% difference! (And is currently what $50 will get you)
I'm not sure if the ludicrous "fees" are being charged by Simplex for use of the service, or if they are set by Mycelium or what... but come on guys, surely you need to make sure that the services you are offering are actually a worthwhile for your users!