I would strongly suggest that you invest in the Solex app. You will be able to bring up to date with the latest Arducopter version of software for Solo, even if using the stock Cube with ESC issues, to maximize potential and the app is continually being updated to bring online new abilities and features. I've had the app since the beginning and am blown away by Kelly's improvements to the app and Solo's functions during the last few years. Simply amazing.
I already have the Solex app. I'm still trying to figure out how to use it. I have had my drone for maybe 3 weeks now and all I can get it to do is beep constantly and flash some lights.
So I bought another Solo that was used and it works great. But I am not going to try to pair it to my phone because I think it will start asking for a preflight update too.