The Samsung Galaxy Z Fold3 is the first foldable to support the S Pen (or any advanced stylus, really). But it lacks backwards compatibility – you can use only one of two styluses, the S Pen Fold Edition and the S Pen Pro (the latter needs to be switched into foldable mode).
We already established you can't use a different S Pen, but what if you try it the other way around? As it turns out using the S Pen Fold Edition on a non-foldable phone, say the Galaxy S21 Ultra, doesn’t work either.
The phone detects it, but it doesn’t function properly – for some reason the stylus always works in eraser mode.
SPen Fold pen doesn't work on S21 Ultra, kinda. pic.twitter.com/2nif8r91ZL— Max Weinbach (@MaxWinebach) August 16, 2021
The S Pen Pro will work of course, as long as you remember to switch it to the correct mode. Whether or not a software update to the S21 Ultra (and Notes) can fix the issue is unclear.
So, if you have multiple S Pen-enabled devices, the Galaxy Z Fold3 among them, but want to buy only a single stylus, go for the Pro model. It’s larger (so it doesn’t fit the S21 Ultra or Z Fold3 cases with an S Pen sheath), but it does have Bluetooth functionality (which the Fold Edition stylus does not).The S Pen Pro was a switch to select Z Fold and regular modes
You can check out our Galaxy Z Fold3 hands-on review for more details.