Jiří Král

I am using FlorisBoard. The development still seems to be active.

VS code is technically not open-source since it has many proprietary blobs on top. VScodium is the fully open-source version.

I don’t know how much can Revanced be considered open-source except for their Revanced manager app since you still use the patched versions of the proprietary Google apps.

Sorry for being pedantic.

When excalidraw was mentioned in another comment I think it would also be worth to mention tldraw even though I don’t kniw whether it can be counted as an replacement since I never used draw.io.

https://github.com/tldraw/tldraw

On Android, from FDroid you can install an app called Seal

I like ytdlnis more.