From e Foundation website:
"our mobile phones, even when using no Google service, connect to Google Servers tens of times per hour (91 times per hour for an Android mobile with a total amount of 11,6MB of data sent on a single day, and 51 times per hour for an iphone, corresponding to 5,7MB of data sent to Google servers)."
With a reference to:
https://digitalcontentnext.org/wp-content/uploads/2018/08/DC...
f. While using an iOS device, if a user decides to forgo the use of any Google product (i.e. no Android, no Chrome, no Google applications), and visits only non-Google webpages, the number of times data is communicated to Google servers still remains surprisingly high. This communication is driven purely by advertiser/publisher services. The number of times such Google services are called from an iOS device is similar to an Android device. In this experiment, the total magnitude of data communicated to Google servers from an iOS device is found to be approximately half of that from the Android device.
The hackernoon article was really good, thank you for that! It looks like it can integrate into a nextcloud installation, and nextcloud appears as the default for the /e/ install . That is a really nice feature for self hosting, but that also means that the data on the back end is accessible to the folks hosting it.