Yes, we are aware of that issue, and have done what we could to minimize its occurrence -- and, as explained above, in the most recent beta version the issue should be eliminated. Note that we don't charge separately for the Android app. Proton paid subscriptions provide you with additional storage, email addresses, and features (https://www.reddit.com/r/ProtonMail/comments/182nykn/proton_...), and you can downgrade to the Free version any time you wish if you are unsatisfied: https://proton.me/support/upgrade-downgrade.