Smartphones may be a growing market when it comes to gaming, but the companies running these platforms seem to have a real problem controlling what kind of content goes up. Android's Google Play market is probably the worst offender, with Google seemingly content to allow developers to sell whatever apps and games they choose.
Take Retro Box Studios, for example. This hitherto unknown developer has two titles for sale on the Google Play market which are the property of Nintendo — right down to the actual code being sold.
Donkey Kong Country HD is basically the SNES version of Donkey Kong Country, while Super Mario All Stars + World is — as you might expect — an emulated version of the combined cartridge which appeared on Nintendo's 16-bit console.
Needless to say, avoid these games like the plague.