Hello there mikael.k.adolfsson Great to hear you’ve been a long-time Thunderbird user! Transitioning to Thunderbird for Android involves a specific trade-off between Google’s ecosystem features and your local data privacy. 1. Data Residency & AI Training (Server-Side)You are correct regarding the backend: as long as your data resides on Gmail’s IMAP servers, it is subject to Google’s Terms of Service.Scanning: Google’s automated systems scan incoming/outgoing mail for indexing, spam filtering, and security. AI Training: For personal (free) Gmail accounts, Google uses certain 'Smart Features' data to improve its models. Using Thunderbird does not stop Google from processing data that is already on their servers. The Benefit: By using Thunderbird, you avoid providing additional telemetry. The Gmail app collects extensive metadata (usage patterns, device IDs, location), whereas Thunderbird is open-source and does not engage in this type of client-side data mining. 2. Security Features (Server-Side vs. Client-Side)Pre-delivery Filtering: You won't miss the core security. Google’s Spam and Phishing filters run at the server level. By the time Thunderbird fetches your mail via OAuth2/IMAP, malicious emails have often already been flagged or moved to the 'Spam' folder by Google. Thunderbird’s Protection: Thunderbird provides its own layer of security by blocking remote content (like tracking pixels) by default. This prevents senders from knowing if or when you opened an email—a feature often bypassable in the standard Gmail web/app view. 3. Why it improves Privacy (The "Tracker-Free" Client)Zero Telemetry: The primary privacy gain is moving from a proprietary, data-collecting client (Gmail App) to a privacy-first, open-source client.Encapsulation: Thunderbird acts as a neutral gateway. If you eventually decide to migrate to a privacy-centric provider (like Proton or Mailbox.org), you can manage everything in one local environment without Google seeing your interactions with those other accounts.