I use both an iPhone and an Android (Note 9). My Note 9 is my main phone for multiple reasons:
1. Samsung Pay. I can use mobile wallet at stores that don't accept Apple Pay or Google Pay with Samsung's MST (Magnetic Secure Technology). MST was dropped on the S21 line but it's even on low-priced phones like the A51. It's a big deal because I get 3% cashback on all mobile wallet transactions on my credit card, but for a physical card the best I can do is 2% unless I want to get into the hassle of rotating categories of higher cash back.
2. Stylus. I use an Apple Pencil on my iPad, a Windows pen with Windows Ink on my laptop, and the stylus on the Note 9. While Apple is predicted to add Apple Pencil support to future iPhones, it hasn't happened yet. The stylus is more precise when entering text or playing games and keeps the phone cleaner.
3. Headphone jack. While this was dropped starting with the Samsung S20, it still exists on some Samsung, LG, and other Android phones. Yeah, I know I can use an adapter to gain back that functionality on other phones, but I try to minimize dongles.
4. MicroSD Card Slot. I have ripped my entire CD collection to MP3 and it's stored on my MicroSD card, along with audio books and an occasional movie. When traveling overseas I'll load maps onto the MicroSD card. The partitioning of putting content onto the memory card and apps onto phone memory works well and saves money since higher capacity phones are a lot more expensive than a MicroSD card.
5. Apps. There are several apps that I use for which there is no iOS equivalent, either because Apple won't allow the equivalent app or because the hardware to support the app isn't accessible to the developer. Unlike Android, iOS doesn't support Bluetooth SPP (Serial Port Profile) which means many Bluetooth devices won't work. Unlike Android, iOS doesn't allow apps to access NMEA GPS data.
6. Fingerprint sensor. While the iPhone 13 will reportedly get TouchID back, for now only the iPhone SE 2020 has a fingerprint sensor. Even pre-pandemic FaceID was a huge annoyance in countries where mask wearing is common, but with the pandemic FaceID has become a real pain.
7. Apple tends to follow Android in terms of introducing new features. Apple was late with 3G, late with 4G, late with 5G, late with NFC, late with larger phones, late with wireless charging, and still doesn't have 120Hz displays or under-screen fingerprint readers. Those committed to iOS wait patiently for 1-2 years for Apple to catch up with Android devices. In the tech industry, Apple is what we call a "fast-follower."
8. App stores. With Apple, you have to get all your apps from Apple. While this increases security, it means that a lot of more esoteric apps are only available on Android (which is why Android does so well in China).
9. Google Assistant is far superior to Siri.
10. USB-C. USB-C has multiple advantages over Lightning. Hopefully Apple will soon move their phones to USB-C, just like they did for the iPad.
11. Separate audio volume controls. On my Samsung I can set different volumes for ringtone, notifications, media, system sounds, and Bixby (Samsung's personal assistant).
I know that Apple will never add a MicroSD card slot, add MST (Samsung owns the patent), or bring back the headphone jack. But if they would add 120Hz displays, Pencil support, bring back TouchID in some form, and switch to USB-C, it would go a long way in converting some Android users over to iPhone. It would also be really nice if they'd allow developer to access NMEA data, add support for Bluetooth SPP, and allow separate volume settings for different functions.
BTW, I also use the USAA app on both my iPhone and my Android phone. I've never noticed any lag on either.
It is true the the Apple Watch is far better than any Android watches, though it's possible to use an Apple Watch with an Android phone by going through a few contortions.