Ever since Nintendo stock holders told Nintendo chief's to start looking at mobile as an option bloggers everywhere have started false rumors that Nintendo will be releasing games or tablets for the Android OS. Officially Nintendo only said it will look into it's options on mobile platform's. The wild stories out there have even been promoted by blogs that usually don't go for stories like this, which in turn made rumors spread throughout the internet on facebook and twitter.
Nintendo's stance has always been to keep Super Mario Bros,Zelda,Metriod, and other 1st party IP on Nintendo hardware only. The only way to currently recieve Nintendo games on android is emulators , which you can find online and on the appstore. You will also find mini-games based on Nintendo charactors online also as a native solution if you don't like emulators. There will be no Nintendo made Super Mario Bros game on Android devices , as Nintendo says the brand will be diluted if it's put on devices that are not properly equipped to play such games.