If you just published your app and wondering where all your widgets go, do not worry. By default, all Gecko theme widget positions are disabled to preserve the precious screen real estate. If you really must enable them, then find these options in WP Admin -> PeepSo -> Configuration -> Mobile App

We do however recommend to keep bare minimum of enabled widget positions, because managing the mobile phone screen space is much different than one on a physical computer and your users might get confused what is what.