Why do you think no one has ever heard of an app just because you haven't? In general, your comment feels rather agressive for no good reason.

That said, i have my doubts about the term 'exponential'. I forgive financial journalists who think that it means the same as 'explosive', but a programmer should know better. Unless, of course, Lucidchart does have exponential growth, in which case i guess congrats are in order.