I believe Xournal++ will be what you are looking for (once it is out of beta). While not open source, there's also Styluslab's Write which saves the files as svg so you can open them anywhere.
I believe Xournal++ will be what you are looking for (once it is out of beta). While not open source, there's also Styluslab's Write which saves the files as svg so you can open them anywhere.