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SignalWire Plays Pivotal Role in Increased Subscriber… | SignalWire

SignalWire Plays Pivotal Role in Increased Subscriber Retention at Robokiller due to Better Spam Blocking

Case Study: Robokiller

Product Marketing Manager

Abbi Minessale
“That’s the first time in our business that we were looking to do outbound calling over VoIP like that at a really large scale. ...We needed something that was reliable, was going to work on day one, and be not just an effective solution but an excellent solution. And so we started looking at vendors and it was very very clear that SignalWire had the reputation in the space to be a great solution for that problem we were trying to solve.”
-Daniel Pannasch, VP of Product at Teltech


Robokiller is a mobile application from Teltech that blocks spam calls through proprietary analyzation and filtration systems. The product had been receiving complaints from customers that it was not aggressive enough in its spam blocking so they released Robokiller 5: an upgrade that addressed these concerns by integrating SignalWire voice APIs. SignalWire allowed Robokiller to block spam more aggressively by sending calls back to users after they had gone through Robokiller’s new call blocking technology. After adopting SignalWire, Robokiller has seen increased subscriber retention due to the reliability and increased effectiveness of the product’s ability to stop robocalls.

About Robokiller

Robokiller is a spam call blocker application available for IOS and android. Robokiller uses audio fingerprinting and machine learning to block spam calls from reaching their customers. The product analyzes incoming calls to their customers, filters out the spam, and sends back the authentic calls using SignalWire Voice APIs.

The Challenge

Robokiller’s goal as a company is to block spam calls from reaching their customers while allowing genuine calls through. Robokiller had been receiving complaints from customers that the product was not aggressive enough as there has been a recent increase in effort from spammers to get around traditional spam blockers by using new methods like neighbor spoofing.

It was important to find a way to battle these new robocall techniques so their customers could have confidence that Robokiller was accurately and effectively blocking spam from their phones.

The Solution

Robokiller 5 is an updated version of the product with a new call blocking system that integrates voice over IP calls to battle more advanced robocalling technology. SignalWire was able to offload the voice integration so that Robokiller could focus on identifying spam.

Robokiller acts as a filter that protects users from robocalls; when Robokiller receives a call, it makes the decision if it is spam or not. After the call has gone through this filter, it is sent back to the customer as a VoIP call using SignalWire Voice APIs.

Sending calls back to customers as an outbound VoIP call is what allows for inbound calls to take a detour through Robokiller’s filtration system before being sent to the customer. This new system has been incredibly effective and has resulted in an increase in long term subscriber retention for Robokiller.

Robokiller 5 was the product’s first experience with outbound VoIP calling and required a reliable and easy to use solution. It required very little effort for Robokiller’s development team to implement SignalWire Voice APIs and it is easily handling the amount of traffic and usage needed to serve hundreds of thousands of customers.

After the success of Robokiller 5, Teltech is now considering building out VoIP functionality for more products in the future.

“SignalWire definitely plays a pivotal role in delivering that [positive] product experience and has absolutely resulted in subscriber retention and growth for Robokiller.”

-Daniel Pannasch, VP of Product at Teltech


Outbound calling

SignalWire handles outbound calls to customers after they have gone through Robokiller’s spam-blocking technology.


    SignalWire reliably delivers authentic calls to hundreds of thousands of Robokiller’s customers.

      Easy to use

      SignalWire Voice APIs are easy to implement even for first-time VoIP users.

      Learn more about Robokiller here.