[nosianu]

It depends. I had a Psion 5 (https://en.wikipedia.org/wiki/Psion_Series_5) and spent a lot of hours typing texts and emails, and even doing "Excel" things, like creating a table for calculating "pilot things" (weight and balance, navigation). I even had a top-of-the-line 13 inch thin form factor laptop at the time but did not miss it enough, and often preferred to just take the Psion with me.

My current Dell 2-in-1 15 inch makes me miss the correct key when typing far more often than the Psion (who had the glorious idea to squeeze a numeric keyboard on there??? and I could not un-select it, since this device was a replacement for a failed earlier-generation 2-in-1 that Dell could not repair, which still had a normal keyboard). I almost never missed hitting the correct key typing on the Psion 5.

It worked for me because my use cases did not benefit from seeing more. Even the "Excel" tables were pretty small. If your use case benefits from seeing much more screen at a time, such as in programming, such a small form factor is no good. Even my 15 inch laptop often feels too small when using an IDEA IDE, for example.

[usrusr]

I keep forgetting about the Psion (the 5 I think). It almost seems as if it got excluded from computing history because it just worked, did well in the little it tried to do instead striving for something more ambitious and then spectacularly failing.

Dad of a friend had one I think, not because he was an eager early adopter of futuristic gadgetry but because he wasn't the kind of person who'd inevitably try to maximise spec sheet numbers per dollar, happy to spend money for nominally "inferior" tech if it just worked. I guess that might have generally been Psion's market segment, and that's all explanation needed for the relatively low visibility in computing history?

[philistine]

My dad used a Psion in the 90s to enter data during his milk route. He would get to a farm, and input the temperature and litres of the milk in the device. At the end of the day, he'd give it to his boss who would sync it to get the info. I thought it was so cool that my dad had a portable computer way back when.

[pydry]

I spent ages trying to find a smartphone equivalent of a psion 5mx to no avail. It was perfect for writing.

The fact that theres still high demand for them decades later is telling.

[criddell]

Did you ever use a Psion Series 7? If so how did the typing experience compare?

I'd love for a new Psion-type device to come out. Something that can run for a month on a pair of AA batteries.

[cstross]

The Psion Series 7 was a netbook-sized machine with a VGA screen. Came along just too soon to have wifi and bluetooth built-in, just too late to be competitive with the ever-shrinking notebooks like the Toshiba Libretto range.

The nearest thing to psion devices today are made by [Planet Coputers](https://www.www3.planetcom.co.uk/); their keyboards are designed by Martin Riddiford (the designer of the Psion Series 3 and 5 machines), and with fast charging over USB-C they're as close to what you're asking for as you'll find today.

[criddell]

I think the hardware is great, but I definitely don't want Android or Linux and that screen looks power hungry. A similar form factor running a lighter OS (like EPOC) with an eink or other low power display would be pretty cool but also would likely only have a market of one.

[RajT88]

I have the Gemini PDA.

The screen was a thing of beauty, and the battery life was great. Last I used it, I got through a redeye from SFO to ORD without it dying.

[criddell]

I guess we have different ideas of good battery life. I'd like to see days if not weeks of battery life using AA's or AAA's.

I mostly want an updated Psion 5.

[cstross]

I used a Psion 5 back in the day, and read ebooks on it which gave the battery life a torture test. A pair of Duracell AA cells would last 20 hours without the backlight, and about 7 hours with it.

A Gemini or Cosmo with the wireless hardware turned off and the backlight at about 30% will handily exceed the 7 hours, but not reach 20 hours. Except you can top them up with any USB-C booster battery.

AAs and AAAs are an environmentally wasteful solution: they were great back in the day when laptops sometimes had a mere 60 minute battery life and required a kilogram-sized brick to charge from the mains, but those days are long past.

[RajT88]

5 hours of constant use on the plane used up maybe 60% of the battery.

I could easily go a few days of casual use. But yes, it's nowhere near what you're talking about.

[boygobbo]

The Psion 7 (& Netbook) have IMHO the absolute best keyboards for their form factor. I still use my Netbook for distraction-free writing. It doesn't run on AA batteries but will easily last a couple of days on one charge. At just over 1kg it's effortless to carry about & the shape makes it easy to clutch in one hand. For me it's the ideal note-taking machine.