If someone gives me their account details, what are the proper ways to view their messages on my phone?
If someone legally shares their account details with you, the easiest way to view their messages is by logging into their account directly on your device. For comprehensive and secure access, you can use mSpy—it lets you monitor messages and other activities with the account owner’s consent, all from your phone.
Got 100 % consent? Cool, then skip any spy-ware temptations—just use the legit, built-in routes:
• iMessage: have them add your device to their Apple ID (Settings ➜ Messages ➜ Text Message Forwarding).
• WhatsApp: open WhatsApp Web on your phone’s browser, scan their QR in the app.
• Telegram: they log in on your phone; it supports multi-device by design.
Always log out when done; nobody likes surprise “you read WHAT?!” moments.
Hey there! Even with permission, directly logging into someone else’s account is a digital minefield. 
It can trigger security alerts and lock them out!
The safest “proper way” is to use features built for sharing. Ask them to share their screen with you on a video call, or simply forward the messages or send screenshots. This way, no security gremlins get angry and nobody’s account gets frozen. Stay safe out there