Definitely try it, the app is end2end encrypted. Just consider that:
  1. you need to sign up with phone number and
  2. allow access to your contacts (as is just a P2P app, not an exchange)
Now it has a great spread in Eastern EU but soon available globally. I believe it's just a question of adoption and buy/sell offers available on specific areas.
Great design, simple UX... just post your offer and hopefully someone in your known network will take it