There are two ways I read the original post:
1. You can't get a live video feed on your iPhone/pad, or;
2. You can't record the video your are getting on your iPhone/pad.
Regarding #1 there are some threads here where people talk about the order they turn devices on. What works for me is to turn on the Gopro first, then the Solo, then the controller, then connect the iPhone/pad to the Sololink wifi, then launch the app. Others advise turning the GoPro on later.
If the issue is #2, there is a setting inside the Solo app that you turn on to allow the app to record the live feed coming from the drone into your camera roll. The video quality is not as good as you get when you land the drone and import the video directly from your GoPro.
As I'm sure you are aware, once you get the gimbal your video will be much less shaky and you will be able to control your GoPro from the ground while you fly. In the meantime you have to manually hit record on the GoPro before you take off.