How to castle while playing on phone?

Hi.

I played a 360 chess game on my phone and I tried to castle. I just don't know how to. It seem it's not the same on the computer. I tried to play my king on the final square but it didn't work. Can anybody help me? Thanks.

I normally do it by holding the steering wheel with my knee, looking out the corner of my eye at traffic. Texting nastly insults to my opponent.

I'm new here so I don't know if this has been answered yet so bear with me.. But you should have to simply choose the king and then choose the square that the king goes to. Either (c1,c8,g1,g8 )

Thanks for your reply. The most useful is the one from LonglslandMark. Or maybe the one from varelse. Anyway, I'll try both ideas!