Check compatibility and install Elder Dialler from Google Play.
The free version provides the core simplified phone experience: large speed-dial buttons, manual SOS calling, Pin Screen and the standard calling and display preferences.
The Advanced purchase keeps all of the free features and enables four highly useful capabilities:
Google Play shows the current local price before purchase. Access to these Advanced features is a one-time in-app purchase, NOT a subscription.
You can start free. Configure the core features first. If you realise later that the Advanced features would be a great help, then just open Preferences and select the feature desired to review the Google Play purchase price.
Compatibility and feature boundaries are based on the current Elder Dialler source. Store availability and the displayed purchase price are controlled by Google Play.