VisiCalc should get the credit: Lotus 123 and Excel are both derivatives that would not exist without VisiCalc (though it’s a given that someone else would have come up with a similar concept ex nihilo around the same time, imo).

Lotus Notes is awful. It’s Exchange, but worse. They wanted it to be an “open” platform for applications to be built on top of but failed to win over hearts and minds (and especially not hearts...).