On their webpage it has the iPhone 5s 16gb for $249.99 + $50 off and $100 Account Credit. Should only be $100, not $150...
They have no good Android options atm price wise. Looking at Swappa for a used Sprint phone (which should work on Boost since they are a subsidiary) there are some other choices (ie, HTC M9 for $215, Galaxy S5 $120, Nexus 5 $160, LG G3 $119, Note 3 $145, HTC M7 $70) but those would then require you use your "credit" for air time instead of a device if that is possible. Used iPhone 5s's are going for $135 btw so you could buy it, sell it and buy something else but that sounds like a pain in ze proverbial ass.