OnePlus 6.
I used Android since Gingerbread (first with a Galaxy Tab) and was big into custom ROMs. My last Android for a while was OnePlus 5, and I went to an iPhone 6s. I became an Apple fanboy for a while after that as Apple had the experience I've been trying for years to get on Android! I got an iPad, Watch (S1, S3, S7), iPhone SE, and finally to a SE 2nd-gen. The experience was so great I got bored of it, and bought a OnePlus 6 about 5 months ago and use it today.
I enjoyed the clean stock apps on iOS, and the walled-garden approach made the App Store feel relatively safe; I didn't feel I had to scrutinize app developers and permissions as-hard when checking out new apps on iOS. For anyone not tech-savvy, I overwhelmingly recommend iOS just because Apple's entire ecosystem is more secure overall and protected consistently than Android.
I went back to Android because I enjoy tinkering with my devices. I chose a OnePlus 6 because it had 8GB of RAM, was OLED, and has support for (mostly?) every mobile OS solution available currently (LineageOS, Ubuntu Touch, Project Renegade for Windows and Linux, postmarketOS). My main set-up is LineageOS without Gapps and a few apps from F-Droid, and I like it because of the control and privacy it gives me. It's gross flashing Gapps and Google having full system permissions and full-reign on system settings just to provide a few apps from Play Store, and was downright insulting having Google (Pay) tell me I can't use my device to pay at card terminals because
they think it's insecure. And ironically if I go flash some additional stuff like Magisk, my device will be "secure" as if that makes sense. Basically, I like the freedom of Android without Google apps!
Any modern Android device and folding screen stuff isn't on my radar unless they advertise full LineageOS support or mainline Linux, at a price ponint that makes sense. $200 for a 128GB 8GB OP6 makes sense. $400+ for a Pine Phone Pro with 4GB RAM isn't happening when OP6 exists. I'll likely go back to iPhone though before another Android, unless there's a 4G/VoLTE cellular 7-inch tablet (phablet) that supports LineageOS, Windows, or even mainline Linux; 7" is my favorite form-factor and I'd pay almost anything for that today