I know proton bridge works on desktop but it doesn't on iOS or Android. Can you make this work on Android? Or make a plugin for Thunderbird on Android?

Your mail app on Proton lacks behind in many features that other mail clients have and would require Proton to allocate significance resources to improving and maintaining your mobile app. Even the requests in this forum asks for lots of features that already exist in other mail clients like Thunderbird.

Thus, can you either develop the bridge for Android or plugin in thunderbird that will allow integration of proton mail as a mail and calendar account?

If there are security risks, then please explain and allow your users to make the decision whether or not to install your potential solution on their mobile or stick with the app. I, for one, may accept the risk.

Thanks!!