Notify Lite

This application will display a popup window for missed calls, text messages,
calendar events and emails via https://f-droid.org/packages/com.fsck.k9. It is extremely customizable
with many options to suit your needs and style. Extra themes are available as
apks from the website.

Anti-feature: Addons. The app has some limitations and the user is prompted to
install the fully-featured proprietary version.

Status: Newer versions have been published by the author but without source
code.

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