Now I use the Motorola Razr 2025. 90% of the time I just keep it closed. The outer screen is 3.6" and a square, but the screen doesn't extend all the way out if you keep the hinge on the side. It's kinda heavy at 6.6oz (compared to the Palm Phone's 2.2oz), but with a ring, it's super easy to use one-handed. And it has battery life and compute power to handle today's unnecessarily compute-heavy apps. You can also split apps in half when it's open so you can just use them on the bottom half of the phone.
Pictures:
https://www.middleendian.com/phone.jpg
https://www.middleendian.com/phone-with-keyboard.jpg
Main disadvantage is that when it's closed, you only have a "selfie" camera as the back camera is facing you and the front camera is inside. So it's hard to quickly take pictures of things I see outside (usually funny birds). Other annoyance is that if you open the phone, use it, and then close it, the outer keyboard resets to the default keyboard and you need to "change the keyboard layout" to get it to use your preferred keyboard (Microsoft Swiftkey in my case)