Role: Senior Android VoIP / SIP Engineer

Experience: 10-16 years

Location: Pan India

Work Mode: 4 days Work From Office (WFO)

Interview Process

1st Round: Virtual

2nd Round: In Person

Job Summary

We are looking for a highly experienced Senior Android Engineer with strong hands-on expertise in Native Android development, SIP/VoIP, Android audio, Bluetooth, Android Enterprise, and networking.

The ideal candidate should have experience building or maintaining production-grade SIP/VoIP applications, particularly products involving Push-to-Talk (PTT), dispatch, radio replacement, or field communications.

This is a hands-on technical role requiring strong knowledge of the Android platform and the ability to troubleshoot issues across the application, audio, network, Bluetooth, SIP signalling, and RTP/SRTP media layers.

Must-Have Skills

1. Native Android Development

10-16 years of overall software development experience with strong hands-on Android experience. Strong development experience in Native Android using Kotlin or Java.

Experience developing and supporting production Android applications.

Strong understanding of Android platform-level capabilities.

Experience with

Foreground Services

Background execution

Doze mode

Audio focus

Android lifecycle

Background restrictions

1. SIP / VoIP

Hands-on experience building or maintaining a SIP client/application.

Strong understanding of

SIP signalling

RTP / SRTP

Call setup and teardown

Media negotiation

VoIP call flows

Ability to analyze packet captures/Wireshark traces and troubleshoot SIP or media issues.

Solid understanding of common VoIP problems such as one-way audio, call drops,



media failures, NAT/network issues, etc.

1. Android Audio

Strong knowledge of the Android audio subsystem, including:

AudioManager

Audio Focus

Audio routing

Speaker/handset routing

Bluetooth audio routing

Wired/Bluetooth headset handling

Troubleshooting one-way audio and audio routing issues

Understanding how Android manages audio during calls and background activities

1. Android Enterprise

Hands-on experience with Android devices in a managed enterprise fleet, including:

Android Enterprise

Device Owner

Dedicated Device / COSU mode

Managed configurations

MDM-deployed applications

Enterprise device policies and restrictions

Understanding what Android Enterprise modes allow or prevent an application from doing

1. Bluetooth

Experience developing applications that interact with Bluetooth accessories/headsets.

Strong understanding of

HFP / HSP

HID

Bluetooth pairing lifecycle

Bluetooth connection/disconnection handling

Headset routing

Handling headset disconnection during an active call

Re-establishing or changing audio routes after Bluetooth events

1. Networking

Good understanding of networking concepts relevant to real-time communications: Wi-Fi

Wi-Fi roaming

Packet loss

Jitter

Latency

Network interruptions





RTP/media troubleshooting

Impact of network conditions on VoIP/PTT communicationStrongly Preferred

Hands-on experience with WebRTC.

Understanding of when WebRTC is suitable and when it is not the right solution for Push-to-Talk (PTT).

Experience working on

Push-to-Talk (PTT)

Dispatch systems

Radio-replacement products

Field communication platforms

Mission-critical communication applications

Exposure to Cisco CUCM.

Experience integrating Android communication applications with Cisco CUCM or enterprise telephony platforms.

Experience with real-time communication and audio/video technologies.

Key Responsibilities

Design, develop, maintain, and troubleshoot native Android VoIP/SIP applications.

Implement and maintain SIP signalling and RTP/SRTP media functionality.

Diagnose complex audio, Bluetooth, SIP, network, and background-execution issues.

Analyze packet captures and identify SIP/media/network problems.

Develop reliable audio routing across speaker, handset, Bluetooth, and other accessories.

Ensure applications work correctly under Android Enterprise managed-device restrictions.

Work with MDM/Device Owner/Dedicated Device configurations.

Handle Bluetooth headset connection and disconnection scenarios during active calls.

Optimize applications for Wi-Fi roaming, packet loss, jitter, and unreliable networks.

Collaborate with backend, telephony, networking, and product teams.

Contribute to architecture and technical decisions for real-time communication solutions.

Support production troubleshooting and root-cause analysis.

📌 Android VoIP / SIP Engineer (Gurugram)
🏢 Willware Technologies
📍 Gurugram