There is a library available at https://github.com/mbramwell1/GeoFire-Android

The location of each document is stored using the following formula (a method is provided by the library itself):

degreeMatch = (latitudeDegrees + 90) * 180 + longitudeDegrees

I did a few tests combining a few operators (including limit and array-contains) and it seems to be returning the correct results.

I am currently filtering some data using GeoFirestore for Android. By decreasing the radius, of course it is possible to decrease the number of documents retrieved. However, I would like to further filter the same data using the compound queries functionalities provided by Firestore or simply limit the number of reads using limit(), in order to 1) avoid downloading/reading documents that are no needed and 2) improve my users’ experience in terms of time and resources.

I know this question has been already asked several times (for example, here). Nevertheless, Firestore is rapidly evolving—for this reason I would like to ask if there are updates regarding this topic.