When I founded ebuddy.com, with about 400 million registered accounts, it actually started as a hobby. I was bored as hell at my 9 to 5 software developer job and I started a side project that eventually became a multi-national company.
Fast-forward to today and the story didn’t change that much. More grayed hairs for sure, gained a few more pounds, maybe not so bored — my 2 kids always make sure that doesn’t happen — but I still make myself busy, keep building new stuff, launching here and there new projects.

What is Yelo?

One of the projects I'm working on, Yelo Phone or just Yelo, started a couple of new years already. I've been working on it on and off, but this project actually fulfills a need that I had a struggle with and I've been using it regularly.

It started when one day I left my Android smartphone at home. Doesn't happen very often, I have to admit, but that's not the point. I could still send and receive SMS messages via MightText ("The iMessage for Android") so I sent an SMS to my wife: "Honey, I left my phone at home, but you can still text me"

This innocent SMS message changed everything. My wife — which is married to a uber geek — is not very tech savvy, so she kept thinking about how I was able to send SMS without my phone and when I came back home I had to explain how apps like MightText and iMessage work. Her immediate reaction was: "so if it works for SMS, why doesn't it work for calls?"
"That's brilliant" I thought to myself. I looked around and couldn't find anything that worked like that, so a new project started and I called it Phorgot.

This is back in 2013. I pulled something together that was kind of working, but let's face it, I don't forget my phone that often and I didn't see much use of it so I left the project in standby.

Then I moved from The Netherlands back to Portugal in 2014. I still wanted to be able to answer my calls from my Dutch phone, so my options were:

  1. Carry 2 phones — It’s not ideal, managing one phone is already enough and I still had to pay roaming charges whenever I received calls from my Dutch phone
  2. Forward calls to my Portuguese phone — That would also be a little bit expensive and I'm not even sure if my operator allows forwarding to international numbers.
  3. Dual SIM phone — Not an option if you want a sexy phone like Samsung Galaxy S7 or iPhone 6s and I would still have to pay for roaming.

The Solution?

So that's where Yelo (it was actually called Phorgot and then Phonnix ) comes in handy. Usually, SIM cards come pre-configured with conditional call forwarding pointing to the operator's voicemail system that picks up calls that we can't answer for whatever reason. All I needed to do was to setup conditional call forwarding on my Dutch number to point to a Dutch Yelo number and through VoIP I can answer the calls on my Portuguese phone with the Yelo app installed on my Android without paying roaming fees.
My Portuguese number is also configured with conditional call forwarding pointing to a Portuguese Yelo number so when I'm in The Netherlands I just need to switch SIMs and if someone calls my Portuguese number I can answer the calls with the Yelo app just as well.

This was the main reason why I was using Yelo but it has a couple of other use cases even if you just have one phone:

  1. If you want to save roaming costs while you're abroad you can setup call forwarding and answer calls via WiFi
  2. If you work or live in an area with poor network coverage you can also make or answer your calls via WiFi if call forwarding is configured
  3. If you left your phone somewhere or run out of battery you can answer your calls on a web browser or other Yelo devices
  4. It's also possible to make VoIP calls using any of my numbers as the caller ID — So if I'm using my Portuguese SIM card and I want to make a call using my Dutch number and vice-versa I can use Yelo.

What about competition?

Yes, there are already some players in the market.
Let's start with the most obvious, the operators themselves. Some operators have invested billions in IMS. It allows operators to build applications on top of IP such as WiFi calling or VoWIFI/VoLTE. It has plenty of advantages, as you can imagine, but it's very heavy on the infrastructure side and Yelo is operator agnostic, it works with any operator as long as it supports call forwarding (invented in 1973) and it works on any Android device or modern web browser (iOS is still work in progress).

There are also other apps doing similar things, but Yelo is the only one supporting multiple numbers in a single account. It's also the only app that supports making and receiving calls using web browsers. It also has a more advanced voicemail system than other solutions currently available when calls can't be answered.


What kind of technology is behind Yelo? Well there's the telecommunications layer obviously which is supported by Twilio.
The backend infrastructure is handled by AWS Elastic Beanstalk on Tomcat 8 (yes I'm a Java developer) and some bits of the platform is on Google App Engine.


I've been using Yelo for the last few months and it has proven to be quite useful. Still work in progress but if you want to take it for a spin please do, any feedback is highly appreciated. I would love to make it free but it costs money to make and receive calls.
The most important, from my perspective, is to learn from the projects I'm involved and, surely, I learned a lot from this experience. I'm thrilled to have developed something like this, it's very satisfying and if it happens to help other people with the same issues even better, I know I'll keep using

Happy Call Forwarding

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