Update webkit separately from android. Maybe?

Question

Android

The problem is the following.
The company has several dozen tablets for official purposes. The devices are quite old, but they do their job.
It costs android 4.2.
The company also has several html5 web applications that are planned to become full-fledged applications for ios and android in the near future with the help of some kind of mother and phonegap.
But the problem is that due to the antiquity of webkit on android tablets, the application works extremely crookedly.
Updating devices is not realistic - China, to which updates are not released, and all sorts of CyanogenMod are not suitable.
In the process of comprehending the problem and finding a solution with little bloodshed, the idea came up to try to somehow update the webkit separately from the system. The only question is how :)

Answer 1

Starting with Lollipop you can , older is more likely not.