I am using ionic 3 android build apk and trying to laod image from file:///storage/emulated/0/data/io.ionic.vdeovalet/cache/image.jpeg
I had the same issues and it turns out that The new ionic webview plugin is the cause for the problem.
The new plugin: cordova-plugin-ionic-webview @ 2.x seem unstable...
to get it working downgraded back to cordova-plugin-ionic-webview@1.2.1 and all should work
Steps:
1. uninstall webview
ionic cordova plugins rm cordova-plugin-ionic-webview
2. install old one:
ionic cordova plugins add cordova-plugin-ionic-webview@1.2.1
3. clean cordova
cordova clean android