Ionic 2 still uses web browsing. Things have become faster and newer devices, of course, faster. Ionic does some wonderful things, but you will have a more efficient application using NativeScript IMO. I don’t have tests right now, but I can assure you that someone has tests. NativeScript is likely to win on all fronts, because it's not web browsing. This is similar to the reaction of the native and xamine. As with most options, it depends on what you need and the factors of time, cost, etc. All of these frameworks have pros and cons. Personally, I settled on NativeScript, since I did not know that I was reacting to the native reaction, and I wanted to have my own user interface, and not related components in the web view. However, for a quick prototype or application that you may havewant to reuse as a PWA (progressive web application) is a good choice in this regard. Of course, you can reuse the code with them using angular and react to the reaction, but the user interface is different from the fact that it is not shared with the web DOM. Hope this helps.
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