Senior Android SDK Engineer – Network Measurement

Ziff Davis, LLC; Madrid; On-site; EUR 90,000 - 130,000; Full time

Job summary

Ookla is seeking a Senior Android Engineer to own the Android SDKs for CQoE and Speedtest. You will work across Kotlin/Java, JNI/NDK, and a shared C++ engine to implement and maintain measurement features across Android, iOS, and embedded targets.

You will design robust APIs, ensure safety, privacy, and verifiable results while delivering end-to-end features with strong quality controls.

Qualifications

• 5+ years of software development experience.
• Experience with Android using Kotlin and Java.
• Substantial experience building and maintaining SDKs or libraries.
• Strong data literacy: SQL proficiency and Python for data analysis.
• Curious, proactive stance toward AI and modern engineering practices.
• Excellent debugging, troubleshooting, and data analysis skills.
• Strong time management and self-driven work ethic.

Responsibilities

• Design, implement, and maintain network measurement features in the CQoE and Speedtest Android SDKs.
• Work across the JNI/NDK boundary into the shared C++ measurement engine.
• Contribute to testing, documentation, deployment, and development support.
• Roll out SDK changes behind feature flags with quality checks and post-release verification.

Skills

Android Kotlin

Android Java

SDKs/Libraries

SQL

Python

AI mindset

Debugging

Tools

JNI/NDK

C++

Job description

Ookla is seeking a Senior Android Engineer to own the Android SDKs for CQoE and Speedtest. You will work across Kotlin/Java, JNI/NDK, and a shared C++ engine to implement and maintain measurement features across Android, iOS, and embedded targets.

You will design robust APIs, ensure safety, privacy, and verifiable results while delivering end-to-end features with strong quality controls.