If anyone is interested to see the WASM + canvas renderer performance compared to Android/iOS builds, I've build my app for the web.

The web app is here: https://app.vocabuo.com (completely free) And the links for Android/iOS builds are here: https://vocabuo.com (soft paywall)

To an untrained eye who does not care about dropping a few frames, the web version is almost indistinguishable from the "native" build. Especially if you add it to homescreen from safari to hide the navigation bar.