How To Build A Custom VoIP App For Your Business?

mohamedasar Published On February 28th, 2025 Tech Talks

Discover what exactly you need to build a VoIP app to drive unlimited conversations around your business. This free guide walks you through the process of preparing, organizing and launching your audio calling platform to enable user interactions in real time. 

• VoIP basics, and its working process
• Key development steps
• Bonus: strategy to build the app in 48 hrs

What Happens When Businesses Switch To VoIP?

• 70% reduction in communication costs
• $1000 saved per employee
• 50% lower cost per traditional phone line

The numbers prove why your decision to build a VoIP app is indeed a wise idea. To get started, let’s first understand what does VoIP have to do with setting up communication at such low cost and efficiency. 

What Is Voice Over Internet Protocol Or VoIP

As per Jeff Pulver, a pioneer in VoIP technology and co-founder of Vonage,

“VoIP is not the next big thing. It is the big thing.” 

VoIP, otherwise known as IP telephony, is a technology that uses the internet to transfer voice data packets to enable voice communication across devices. The modern mobile infrastructure, 4G and 5G, relies on VoIP for voice transmission. 

Since 1995, VoIP started replacing POTS (Plain Old Telephone Service), popularly known as PSTN (Public Switched Telephone Network). The traditional telephone system was complex to set up and slow, as they used copper wires, and the signals were analog. 

VoIP does not need any such physical infrastructure for voice transmission. Above this, VoIP supports multiple forms of communication, including SMS, fax, and voice messaging, in contrast to traditional telephones that could only enable phone calls. 

On the other hand, businesses will only need an app (softphone) like Google Voice, Microsoft Teams, Skype, or Viber installed on their systems to enable voice communication across their organisation. 

Apparently, there’s no need to discard their traditional phones; rather, connect them to the internet using an adapter and convert them into VoIP phones (hardphones). 

However, in some cases, the apps might not always be convenient and secure in a business setting, and that’s one reason why 53% of them, like yours, are building their own custom-built voice calling apps. 

Case Study: Utah State University’s VoIP Transformation

Challenge:

Utah State University faced high costs and inefficiencies with its traditional analogue phone system. Frequent trouble tickets and office relocations consumed valuable IT resources, increasing labour expenses and reducing productivity.

Solution:

The university implemented a VoIP solution, automating troubleshooting and simplifying office moves.

Results:

• Saved hundreds of thousands of dollars in operational costs.
• Reduced labour expenses by $120,000 per year by minimising IT support needs.
• Recovered 80 hours per week for the IT team, allowing focus on strategic initiatives.
• Enabled seamless office moves, with faculty and staff simply plugging in their phones at new locations.

Source:Forbes

How Does VoIP Work?

In simpler terms, VoIP works like this:

• Your voice is digitised and sent over the internet.   
• The internet acts as the “phone line”.    
• The digital data is converted back into sound at the other end.

When you put the working process through the lens, this is what VoIP communication looks like. 

Key Components In A VoIP Set Up

• Internet: A stable internet connection for clear voice quality. 
• VoIP Device: A computer with a microphone or speaker, or a regular phone with an adapter. 
• VoIP service provider: A company that provides VoIP services and manages calls. 

Here’s a breakdown of how it works:

1. Analog To Digital Conversion 🔁

• You sit in front of a computer, hit that call button on your app, and start speaking. Your computer’s mic picks your voice (analogue) and feeds it into the app. 
• The VoIP app converts these apps into digital data packets.

2. Data Packet Transmission 🛜

The app, which works on the internet, sends it to the recipient device, using the metadata (typically the details of the intended recipient device).

3. Routing and Connection ⛓️

At this stage, there are 2 possibilities:

• If you’re calling a VoIP user, the packets are directly sent to their device over the internet. 
• If your callee uses a traditional phone, the VoIP provider converts the digital packets back into analoguesignals before sending it to their regular phone network. 

4. Reconversion And Voice Output 🔊

• On the receiving end, the digital packets are reassembled in the correct order.
• They are converted into analogue voice signals, which the person at the other end of the call can hear through their phone’s speaker or a headset. 

Interesting? 

Let’s quickly look into whether VoIP is a good suit for your business. 

Pros

👍 A lot cheaper than traditional phones for international calls.

👍You can use it anywhere with an internet connection.

👍 Enjoy modern features like call forwarding, voicemail & video conferencing. 

Cons

👎 A weak internet connection can spoil the call experience. 

That’s all the basics you need to know about this amazing technology. It’s time to learn the steps for building an application that runs on VoIP. 

6 Steps To Create A VoIP App in 2025

Anything that’s planned correctly will meet its perfection—this goes well with understanding and preparing for your VoIP app development.

To help you with the process, here is a breakdown of the steps to build a complete VoIP app. 

1. Start With ‘Why’

[ ⏳Timeframe: approx. 1 week ]

An idea isn’t just enough. You must put your idea through the lens and identify the goals of building a VoIP app.

Prepare a development plan; analyse the purpose:

• Who will be the target audience for your app? Your team or customers?
• What features are you going to add? Split them in phases. 
• What is the scale of your app in different phases?
• Determine the budget; more importantly, have a cutoff.
• Fix a deadline for the launch

2. Select The Technologies 

[ ⏳Timeframe: approx. 1 week ]

VoIP apps are indeed tech-heavy. Using the right ones can save you a lot of time and resources. Here are a few recommendations. 

• Programming Languages: Java, Swift, Kotlin, or React Native
• Voice transmission protocols: SIP (Session Initiation Protocol) or WebRTC (Web Real-Time Communication)
• Codecs: G.711, G.722, G.723.1, G.726, G.729, or GSM 
• Storage DB: MySQL, PostgreSQL, or MongoDB
• Cloud Platform: AWS, Google Cloud, or Azure

3. Design Intuitive UI & UX

[ ⏳Timeframe: approx. 2 weeks ]

An app that’s not easy to navigate is simply a waste of time and resources. That’s a good enough reason to build a user-friendly interface while personalising it with your brand elements for an integral experience. 

4. Build The Features

[ ⏳Timeframe: approx. 8-20+ weeks ]

🌟Important –  Add the core features

You know the business requirements, yet it is important to make sure your essentials are covered. 

Add voice calling, video conferencing, instant messaging, file sharing, contact management, call history and logs.

Optional – Add Advanced Features 

Users look for more and your business will have unique requirements. Go for modern voice calling features like call recording, call forwarding, voicemail, conference calling, screen sharing and CRM integration. 

Remember, a few VoIP providers also allows you to go unlimited with third-party plugins and extensions, allowing you to extend the capabilities of your audio calling platform. 

💡Bonus: Do More With VoIP

1. Add offline functionalities for usability during spotty connectivity.
2. Cancel out noise & transcribe audio with AI.
3. Monetise beyond subscriptions with premium features & partnerships.
4. Use sensors & offer location-based services.
5. Gamify your calls. Add engagement elements.

5. Set Up Security Encryptions

[ ⏳Timeframe: approx. 2-4+ weeks ]

As much as technology is growing, so are the security concerns. Although your VoIP app is advanced to make modern voice communication possible, it needs to be protected. 

Use end-to-end encryption like AES to protect the voice data, authentication to prevent unauthorised access, regulatory compliance like GDPR, CCPA and HIPAA, and regular security audits. 

6. Test, Deploy & Launch

[ ⏳Timeframe: approx. 4-8+ weeks ]

• Basically, your development would be complete when you finish step 5. However, there are good chances that the app might have bugs, which, if unattended, would corrupt the entire effort. 
• Verify that all features are working as they should, evaluate user experience, and identify security vulnerabilities if there are any. 
• Once the testing is complete, go ahead, give your app to the world. Deploy your app on cloud platforms like AWS or Azure. —publish on the iOS App Store or Google Play Store. Promote it everywhere your target audience is. 
• Post launch, continue with maintenance, customer support, and regular updates. 

Building a successful VoIP app gets efficient with clear vision and the right tools, and this is where VoIP solutions like MirrorFly come in. Here is a section that discusses how MirrorFly can make the VoIP app development even more effective. 

Role Of MirrorFly In VoIP App Development

The development of a VoIP app takes roughly 4-9 months to complete. MirrorFly shrinks the timeframe to 48 hrs, without any limitations on the customisation. 

It’s true technology is evolving and MirrorFly’s SIP/VoIP solution is a product of advancement that saves both your time and resources, without compromising on the experience that you intend to deliver to your users. 

 As per Fortune Business Insights, the VoIP market is projected to grow from $85.2 billion in 2021 to $102.5 billion by 2026, driven by the increasing demand for remote work solutions and cloud-based communication platforms.

MirrorFly, a leading cloud communication solution, curates the solution, replacing every pain point with your traditional phone system or manual VoIP app development with a custom solution. 

• Limited Mobility and Flexibility: Customise any part of the solution and communicate from anywhere. 
• High Communication Costs (Especially International): MirrorFly reduces both the development costs and the communication costs by 50%.
• Lack of Feature Integration: MirrorFly’s solution comprises 1000+ features including video, voice, instant messaging, SIP/ VoIP, activity feeds & live streaming.
• Poor Call Quality (Sometimes): Adaptive frame technology that takes care of call quality, delivering average respone time and latency less than 100 ms. 
• Complex Setup and Management: Integrate in 10 mins, and move on.
• Security Concerns: MirrorFly comes with built-in encryptions like AES and SSL. Above this, you can customize the security as per your business needs. 

This list is a glimpse into how MirrorFly can impact your VoIP app development strategy. But there’s more this solution could do – like on-premise deployment and full data ownership.

You can get on a quick call with MirrorFly experts and explore if the solution can work wonders with your app development. 

Happy developing! 

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