MQTT Android App Development

I need an Android app developed using Android Studio that connects to an MQTT server. The app should subscribe to topics and receive control commands.

Key requirements include:
- Run in the background even when closed
- Send notifications when certain conditions are met
- Ability to subscribe to MQTT topics

Ideal skills and experience:
- Proficiency in Android development (Java/Kotlin)
- Experience with MQTT and background services
- Knowledge of implementing notifications