We did a lot of research and came to the right conclusion that SPY24 is the best app to spy on WhatsApp messages without installing it on the target phone. It has the most features and is the most cost-effective option. To start using it, all you need are the iCloud credentials of the person you want to track. You put them into your properly encrypted SPY24 account and get access to their phone and WhatsApp activity 24 hours a day, 7 days a week.