I have been building Kitaphone a web app that lets you call regular mobile and landline numbers directly from your browser. The idea is simple, there are still plenty of situations where apps like WhatsApp, facetime and other internet calling apps aren't an option. For example, when you are abroad and need to call your bank, an airline, or a government office or your son/daughter's school.
I wanted to make those calls possible without requiring users to install another app or buy a sim card or even commit to a monthly subscription. I built Kitaphone using Next.js and Twilio, One of the more interesting challenges has been making browser based calling reliable, especially when it comes to dealing with microphone permissions, sending keypad inputs to automated phone systems, and preventing abuse of free calling credits.
The product is live and supports international calls to regular phone numbers, users currently need an account to make calls partly because each call has a real telecom cost. I am still improving it and learning from the people using it by receiving feedback.
Fun fact: "kita" means our in Bahasa Malaysia, since I am based in this beautiful country and their people are so warm and welcoming I was truly inspired by this place and decided to name it our phone.
Interested to know or receive feedback from HN folks who worked with WebRTC or VoiP in the past.