how to cast from samsung s2 and ipad mini to chromecast? A friend has just bought chromecast.

we understand we need to download chromecase browser extension 

and it would be easy to watch a special chrome tab from our PC.

but how can he cast from his smasung s2? and from his mini ipad?

any additional app we should consider? like AirCast?
If you want to watch videos that are located on an android phone or tablet, the LocalCast Media 2 Chromecast app will stream videos from your device to ChromeCast.
Note that not all formats are supported and that the performance depends on the device (may be slow if old) and on the WiFi connection.