How to stream from an Ipad to multiple Airplay devices/speakers

[Heiole]

I got a Ipad with a iOS 6.1.2. I have Spotify installed on the Ipad. I currently stream music to my stereo system using Apple TV, which works perfect. But, I would like to install a few more network based speakers in my apartment and stream to multiple airplay speakers simultaneously. This is something which Airplay does not support, one can only stream to one device/speaker at the time. This is disappointing. I know there is a app called airfoil that solve the problem when using a mac or PC as the streaming source, but this app does not seems to be available for Ipad or Iphone.

So, any good suggestions how to solve this?

Thanks

Regards

Ole