[jve]

Well, you have to establish chain of trust to use ANYTHING. By using whatsapp, you trust:

1. FB Won't push code that relays your messages somwhere

2. Google won't backdoor your Android

3. Some networking driver does its job

4. Broadband manufacturer hasn't introduced hardware backdoor

5. Hope GOV won't ask things to FB

Sure there are tons of more points. But the good thing is, everything else out of this circle has a really hard time penetrating your privacy.

[palata]

I guess the point of the parent is that if the client was open source, one could audit it.

But you're right, you need to trust something at some point (be it your hardware, at the lowest level).