I had downloaded version 5.1 from XDA, and each time I had attempted to enter my city, first manually, and then automatically, however Simple Weather keeps on crashing on me.
This does not happen with version 4.1, which is the latest version on F-Droid.
I'll gladly send logs if needed, however I'd rather not make my location publicly available.
Update: I had manually downloaded version 4.1 using APKPure, and then I had set it up without any issues (I saw what you had meant by that the weather maps don't work, which is a shame, but oh well).
Afterwards, I went to update it to version 5.1, however XDA did not register the app as being installed (I presume that the XDA version has a different package name (I did not have time to check)), so I updated it using Yalp Store, and immediately upon opening, the app crashed, and would not open.
The same happened upon updating to version 5.0 with APKPure.
Update 2: I'm sorry I had forgotten to post my system details.
Device: Nexus 4
ROM: CRDroid, Android 7.1.2.
Kernel: SINAI-N4
UnifiedNLP: noGAPPS (I don't use the Play Services in any case)
Location Backends: Mozilla Location Service, Radiocells.org Unified Network Location Provider Backend
Address Lookup Backends: Nominatim
I also have the latest XPosed Framework installed, but no modules that have to do with location.