I'll pick iOS, because that complements my Android experience. In some situations, it's preferrable for mobile app devs to able to work on both platforms. And t

I'll pick iOS, because that complements my Android experience. In some situations, it's preferrable for mobile app devs to able to work on both platforms. And thanks to Flutter, React Native etc, it's relatively easier. I occasionally do backend stuff, though. Sometimes in PHP, sometimes in Go. On the other side, not familiar with .NET development scene. At least on Indonesia, it's not that popular. Major established companies like telcos and banks still use Java, while the cooler startup folks prefer Node, Go, Ruby etc. I suggest you try iOS first, simply because Go still lacks manpower/resource for mobile dev. If you don't like, then try .NET, then :D