If you want the fastest cross-platform native app. Build a native app for each platform and have the design teams review each other's work so everyone stays roughly on the same page.
You're not going to hit your responsiveness goals otherwise. And it's not going to feel native otherwise (if anyone actually cares about that anymore, I dunno)
You're not going to hit your responsiveness goals otherwise. And it's not going to feel native otherwise (if anyone actually cares about that anymore, I dunno)