If you have an Umbrel at home install Snort on it. Then connect to it with Tor browser on your phone. I do and it uses about 1/8 the data compared to Amethyst. Your Umbrel will still use tons of bandwidth but only uploads to Tor browser on your phone the data for each note once. On Amethyst and on the Umbrel it will still download the same note multiple times from each relay.