These exact clones of vintage HP calcs are on my Android phone...

[Vincent Weber]

So ? We are definitely talking way below 10K, not "tens of thousands of dollars". Even 10K is what ? 2 months salary of an experienced développer, spread over more than 7 years ! I know that Olivier spent way more time than that. Nothing shocking to me. When I know the level of détails he spent on de-assembling the ROMs to identify strange behaviour, emulating perfectly all instructions, interrupts and timers, on crafting skins with dedicated Python scripts and drawing annunciators by hand...I've seen the nightmare of emulating the very special memory of the HP-65... I'd rather pay $15 than try to do it myself !

Why not being a bit more grateful for what Olivier did for the community ? Almost all HP calculators (and Sharp) in your pocket !