I am using CrossWalk WebView and as you know it extends the app size of 25 MB more, and the app size after installation goes up to 70 MB!
One thing I need to know, CrossWalk WebView supports old devices, and make the performance much better by using a better WebView instead of the default one, but as I knew after Android KitKat Google replaced the WebView with Chromium one, does that mean that using default WebView in devices running Android KitKat+ is an alternative of using CrossWalk WebView, I mean does the hybrid application performance differ between Chromium and CrossWalk WebView?
If the performance is the same, I would use default system WebView and stop supporting old Android OS.