Ask.fm - Curious? Just ask! Openly or anonymously.
Tellonym - Tellonym is the most honest place on the internet.
NGL: Anonymous Q&A - Fresh take on anonymity!
Whispa.link - Get anonymous messages and honest feedback about yourself.
Sarahah - Sarahah is a Social Networking Application for providing anonymous feedback launched in 2016 and available to use on iOS and Android platforms.
Wire - Private & Secure Messenger