Is it Possible - iPhone Connector Adapter HiFi?

[#1]

I have one of those iPhone / iPod docks on my HiFi and was wondering is it possible to connect to say an android phone using an adapter?
Or anything else non Apple?

[#2]

something like that http://www.amazon.co.uk/gp/product/B00A2LYIIC

[#3]

With that, if it works, I assume you're basically routing through the HiFi's amp / speakers via the phones headphone socket.
I imagined something sort of accessing the files on the memory card directly but I suppose the above is how the iPod dock works anyway?
Similar cheaper version.
http://www.ebay.co.uk/itm/New-30p-female-to-3-5mm-male-end-Audio-Jack-Car-Aux-cable-adapter-Dock-Con...
Of course I just as well use the audio in connector on the HiFi as, thinking about it, the whole point of the dock is so you can control the iPod with the HiFi remote.
I think I've talked myself out of that being a good idea.