

I’ve had nothing but issues with NC instant upload, and stopped using it. It’s error prone and needs constant hand holding for no good reason. It didn’t handle taking a picture and then deleting it instantly very well (and will throw your notifications at you for this, often more than 1). When you have limited connectivity it will utterly confuse itself and ask you to resolve conflicts for 100 files for no reason, when it could just checksum server and client files and notice they are all the exact same. Also when set to only upload on WiFi, and not being connected to WiFi it often still spams notifications that the “upload failed”, despite not being supposed to upload anything. And btw. it could upload files just fine, they failed only because upload on mobile is disabled!
It’s a nightmare. Commonly also referred to as a cluster fuck.
Keepass just uses a (local) file, but it expects and can handle if the file is modified externally. That’s important because it means you can store it on a network share, or in some sort of synchronized storage, self hosted or not (next cloud, sync thing, Google drive, whatever). It’s just up to you. If you have it open on your PC and you add an entry on your phone, your PC won’t “overwrite” it, but integrates any changes you’re making there at the same time.
For example the android client has direct support for a long list on storage services for this exact reason.