NativeScript V8 JavaScriptCore
⬤ Minor difference (1 point) ⬤ Small feature (2 points) ⬤ Medium feature (4 points) ⬤ Large feature (8 points)
NativeScript Desktop browsers
Feature name Current browser NS 6.5 Android
v8		 NS 7.0 Android
v8		 NS 8.0 Android
v8		 NS 6.5 iOS
JSC		 NS 7.0 iOS
v8		 NS 8.0 iOS
v8		 CH 89 CH 90 SF 14 Beta SF TP
Candidate (stage 3)
§instance class fields 5/6 5/6 5/6 0/6 6/6 6/6 6/6 6/6 6/6 6/6
§public instance class fields MDN (Mozilla Development Network) logo  Yes Yes Yes No Yes Yes Yes Yes Yes Yes
§private instance class fields basic support MDN (Mozilla Development Network) logo  Yes Yes Yes No Yes Yes Yes Yes Yes Yes
§private instance class fields initializers Yes Yes Yes No Yes Yes Yes Yes Yes Yes
§optional private instance class fields access No No No No Yes Yes Yes Yes Yes Yes
§optional deep private instance class fields access Yes Yes Yes No Yes Yes Yes Yes Yes Yes
§computed instance class fields Yes Yes Yes No Yes Yes Yes Yes Yes Yes
§static class fields 3/3 3/3 3/3 0/3 3/3 3/3 3/3 3/3 3/3 3/3
§public static class fields MDN (Mozilla Development Network) logo  Yes Yes Yes No Yes Yes Yes Yes Yes Yes
§private static class fields MDN (Mozilla Development Network) logo  Yes Yes Yes No Yes Yes Yes Yes Yes Yes
§computed static class fields Yes Yes Yes No Yes Yes Yes Yes Yes Yes
§private class methods 0/4 0/4 0/4 0/4 4/4 4/4 4/4 4/4 0/4 0/4
§private instance methods No No No No Yes Yes Yes Yes No No
§private static methods No No No No Yes Yes Yes Yes No No
§private accessor properties No No No No Yes Yes Yes Yes No No
§private static accessor properties No No No No Yes Yes Yes Yes No No
§Legacy RegExp features in JavaScript 2/2 2/2 2/2 2/2 2/2 2/2 2/2 2/2 2/2 2/2
§RegExp "lastMatch" MDN (Mozilla Development Network) logo  Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes
§RegExp.$1-$9 MDN (Mozilla Development Network) logo  Yes Yes Yes Yes Yes Yes Yes Yes Yes Yes
§Hashbang Grammar MDN (Mozilla Development Network) logo  Yes Yes Yes No Yes Yes Yes Yes Yes Yes
§.at() method on the built-in indexables 0/3 0/3 0/3 0/3 0/3 0/3 0/3 0/3 3/3 0/3
§Array.prototype.at() No No No No No No No No Yes Flag[1]
§String.prototype.at() No No No No No No No No Yes Flag[1]
§%TypedArray%.prototype.at() No No No No No No No No Yes Flag[1]
§Class static initialization blocks No No No No No No No No ? ?
Draft (stage 2)
§Generator function.sent Meta Property No No No No No No No No ? ?
§Class and Property Decorators 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1 0/1
§class decorators No No No No No No No No ? ?
§Realms No No No No No No No No ? ?
§throw expressions 0/4 0/4 0/4 0/4 0/4 0/4 0/4 0/4 0/4 0/4
§logical No No No No No No No No ? ?
§parameter initializers No No No No No No No No ? ?
§arrow function bodies No No No No No No No No ? ?
§conditionals No No No No No No No No ? ?
§Set methods 0/7 0/7 0/7 0/7 0/7 0/7 0/7 0/7 0/7 0/7
§Set.prototype.intersection No No No No No No No No ? ?
§Set.prototype.union No No No No No No No No ? ?
§Set.prototype.difference No No No No No No No No ? ?
§Set.prototype.symmetricDifference No No No No No No No No ? ?
§Set.prototype.isDisjointFrom No No No No No No No No ? ?
§Set.prototype.isSubsetOf No No No No No No No No ? ?
§Set.prototype.isSupersetOf No No No No No No No No ? ?
§ArrayBuffer.prototype.transfer 0/2 0/2 0/2 0/2 0/2 0/2 0/2 0/2 0/2 0/2
§ArrayBuffer.prototype.transfer() No No No No No No No No No No
§ArrayBuffer.prototype.realloc() No No No No No No No No No No
§Map.prototype.upsert 0/2 0/2 0/2 0/2 0/2 0/2 0/2 0/2 0/2 0/2
§Map.prototype.upsert No No No No No No No No ? ?
§WeakMap.prototype.upsert No No No No No No No No ? ?
§Array.isTemplateObject No No No No No No No No ? ?
§Iterator Helpers 0/35 0/35 0/35 0/35 0/35 0/35 0/35 0/35 0/35 0/35
§instanceof Iterator No No No No No No No No ? ?
§extends Iterator No No No No No No No No ? ?
§Iterator.from, iterable No No No No No No No No ? ?
§Iterator.from, iterator No No No No No No No No ? ?
§Iterator.prototype.asIndexedPairs No No No No No No No No ? ?
§Iterator.prototype.drop No No No No No No No No ? ?
§Iterator.prototype.every No No No No No No No No ? ?
§Iterator.prototype.filter No No No No No No No No ? ?
§Iterator.prototype.find No No No No No No No No ? ?
§Iterator.prototype.flatMap No No No No No No No No ? ?
§Iterator.prototype.forEach No No No No No No No No ? ?
§Iterator.prototype.map No No No No No No No No ? ?
§Iterator.prototype.reduce No No No No No No No No ? ?
§Iterator.prototype.some No No No No No No No No ? ?
§Iterator.prototype.take No No No No No No No No ? ?
§Iterator.prototype.toArray No No No No No No No No ? ?
§Iterator.prototype[@@toStringTag] No No No No No No No No ? ?
§instanceof AsyncIterator No No No No No No No No ? ?
§extends AsyncIterator No No No No No No No No ? ?
§AsyncIterator.from, async iterable No No No No No No No No ? ?
§AsyncIterator.from, iterable No No No No No No No No ? ?
§AsyncIterator.from, iterator No No No No No No No No ? ?
§AsyncIterator.prototype.asIndexedPairs No No No No No No No No ? ?
§AsyncIterator.prototype.drop No No No No No No No No ? ?
§AsyncIterator.prototype.every No No No No No No No No ? ?
§AsyncIterator.prototype.filter No No No No No No No No ? ?
§AsyncIterator.prototype.find No No No No No No No No ? ?
§AsyncIterator.prototype.flatMap No No No No No No No No ? ?
§AsyncIterator.prototype.forEach No No No No No No No No ? ?
§AsyncIterator.prototype.map No No No No No No No No ? ?
§AsyncIterator.prototype.reduce No No No No No No No No ? ?
§AsyncIterator.prototype.some No No No No No No No No ? ?
§AsyncIterator.prototype.take No No No No No No No No ? ?
§AsyncIterator.prototype.toArray No No No No No No No No ? ?
§AsyncIterator.prototype[@@toStringTag] No No No No No No No No ? ?
Thanks to Kangax, webspacedspace, zloirock and the rest of the people who contributed to Kangax ES Compatibility Table

This site uses the base of the awesome compat-table and adds all the code to handle the additional testing on the NativeScript runtimes, and ability to export the data and collate it back to these tables...

[1] The feature has to be enabled via jscOptions=--useAtMethod=true flag.