Privacy experts have found that four out of the five most popular AI companion apps on the Apple App Store may track users' personal data for profit.These AI companions' tracking practices can invade users' privacy and shake their trust in the apps.Among the analyzed apps, Character AI collects the most data, followed by EVA. Nomi claims to not collect data for tracking purposes.Users are advised to be cautious, check app permissions, and be mindful of the information they share while using AI companion services.