HP’s erstwhile calculator division in Corvallis were actually talking about doing this back in the 1980s, when they mooted making a blank Pioneer model available to third-party developers, such as Zengrange, so that we could create niche-market calcs.

I don’t know why they didn’t do it then (since they had many willing and able third-party developers using the HP-41 and HP-71 as a platform for applications, and a custom Pioneer would have been cheaper to make), and I really don’t know why they have done it now. Perhaps some single individual on their dev team, such as Cyrille de Brébisson, made a really impassioned case to management to fly a kite on this; I’d love to know what the business case was that finally worked.

Anyway, despite not having done any serious calculator-related development for over fifteen years, I’m still tempted to get one, and play around with some ideas for custom calcs. I still think there are plausible market opportunities for specialized calculators, and the shirt-losing risk in pursuing them is in the up-front hardware design and manufacturing cost, which it looks like HP has just taken away.