Security & Pen Tests

The security of a product (backend, iOS and Android app) can be evaluated with penetration tests (often done by specialized companies). Android apps are already protected by the Android Sandbox and critical operations like authentication, authorization and content storage should be done in a secure backend, so critical findings in apps are rare. However pen tests will usually produce common findings, that are the same for most apps.

More …

Technical Interviews

Technical interviews have become kind of a meme in the developer community. Especially with Big Tech companies’ extensive focus on niche algorithms and datastructures whiteboard tests, that have no relevance for most developer jobs, but are still copied by non tech companies. This post contains some tips for conducting technical interviews as a developer.

More …

Cryptography & Biometrics

Implementing cryptographic operations in Android without a library can be quite confusing, because the API is based on the ancient Java Cryptography Architecture, which was introduced with JDK 1.1. However from a high-level point of view, encrypting and decrypting data in Android is relatively straight forward.

More …

Bluetooth

Developing Bluetooth apps can be tricky, to put it mildly. This guide is based on my experience working on Bluetooth (LE and Classic) companion apps for devices like headsets, scooters, cars and smartwatches.

More …