Callzo - Your backup call line abroad. No SIM, just open and call.

Hey Product Hunt 👋 We want to be upfront about what Callzo is — and what it isn't. It's not a replacement for your SIM or eSIM. It's a backup. The same way you carry travel insurance not because you expect disaster, but because being in a foreign country with no safety net feels different. The moments Callzo is built for are specific: calling a hotel before arrival, reaching an Airbnb host who isn't picking up, contacting support because the airline lost your bag, or telling someone back home you landed safe — when your regular setup has failed. Small situations. But in a country where nobody knows you, being able to reach someone matters in a way that's hard to explain until you've needed it. Browser-based, real US number, instant activation, no hardware, 40+ countries. Would love your feedback — especially which countries you most need coverage in, and whether the "backup" framing resonates with how you think about travel. 🙏