i noticed I can update a lot of other apps through their new app, but with Zeus I always get this message 
ZEUS v0.8.4-beta2 is now available for testing
- Ability to select wallet/node on start-up
- Currency conversion: Silver (XAG) + Gold (XAU)
- Password page: improve layout
- Revamped Pub theme
- UI improvements
- Bug fixes
## Links
Release notes: https://github.com/ZeusLN/zeus/releases/tag/v0.8.4-beta2
ZEUS documentation: https://docs.zeusln.app/
Embedded node FAQ: https://docs.zeusln.app/for-users/embedded-node/faq
Android
Universal APK: https://zeusln.com/zeus-v0.8.4-beta2-universal.apk
arm64-v8a APK: https://zeusln.com/zeus-v0.8.4-beta2-arm64-v8a.apk
Manifest: https://zeusln.com/manifest-v0.8.4-beta2.txt
Manifest Signature: https://zeusln.com/manifest-v0.8.4-beta2.txt.sig
iOS
IPA: https://zeusln.com/zeus-v0.8.4-beta2.ipa
Apple TestFlight: https://testflight.apple.com/join/vVnODWoi 
Discussion
apk*
also I remember this happened with some of the first 0.8.0 betas but I reported it and you got it sorted quickly :)
Try downloading the apk using .app instead of .com - we changed our domain during the v0.8 testing period
same issue still
Hard to say what else you can try.
Android doesn’t like when you install from different sources, if you installed from Google Play you’re often locked into only upgrading from them.