[zzzmarcus]

I've never used BeeRef or PureRef but if you're on the latest version of OS X and don't need cross platform compatibility, Apple's new app Freeform seems to overlap in functionality with Bee/PureRef quite a bit.

[app4soft]

Freeform looks like a white board app, see OpenBoard mentioned above.[0]

[0] https://news.ycombinator.com/item?id=34983274#34987452