WhatsApp allows you to (optionally) backup your chat history to iCloud or Google Drive. Moving to a new device involves restoring that backup. Your contacts wil

WhatsApp allows you to (optionally) backup your chat history to iCloud or Google Drive. Moving to a new device involves restoring that backup. Your contacts will also have to re-verify your fingerprint. This, of course, is also a way for adversaries to get to your chat history. The backups are not encrypted using a key under your control, so law enforcement could force WhatsApp, Google or Apple to hand over any backups.