-
InfluxDB
Power Real-Time Data Analytics at Scale. Get real-time insights from all types of time series data with InfluxDB. Ingest, query, and analyze billions of data points in real-time with unbounded cardinality.
Android devices could push something like https://gitlab.com/AuroraOSS/AuroraStore or even F-Droid to get a preinstalled store that's not completely evil.
For Linux devices, if you have a powerful enough phone (Pine64, can we please have a really beefy PinePhone?), you could bundle Waydroid + Aurora/F-Droid.
NOTE:
The number of mentions on this list indicates mentions on common posts plus user suggested alternatives.
Hence, a higher number means a more popular project.