# Prerequisites

This is the minimum you need before adding Bubbl.

## Android SDK levels

- Use `minSdk` 26 or higher.
- Use `targetSdk` 34 or higher.


## WhyBubbl depends on modern background location, notification, and WorkManager APIs that are not reliable on lower SDKs.

## Kotlin and Java

- Kotlin 1.8+.
- Java 11+.


## WhyThese match the SDK’s compiled target and avoid desugaring conflicts.

## Firebase

- You must create a Firebase project and include `google-services.json`.


## WhyBubbl uses Firebase Cloud Messaging (FCM) for push notifications.

## Play Services

- Location and Maps libraries are required if you want map‑based geofence visualization.


## WhyBubbl tracks device location to refresh campaigns and geofences.

## Host app referenceThe internal host app uses:

- `compileSdk = 36`, `minSdk = 27`, `targetSdk = 36`.
- Kotlin 2.0, Java 11.


These are safe to use, but you can follow the minimums above if your app cannot yet move that far.