I use an iPad continuously for browsing the web, controlling IoT devices in the home, playing music on the HEOS system, etc.
I live in a place that carriers choose not to serve so I don't spend a lot on a smartphone and plan, sometimes I have a cheap prepaid phone, sometimes I go for years and not renew it. Skype is my preferred way to make phone calls both with my PC and the iPad. It works in most places I want to make a call because public WiFi is available in a lot of places.
The real problems w/ the iPad as I see it are: it refuses to use play music over Bluetooth when using WiFi (Android devices try and usually fail because of interference between the two services) and Apple doesn't allow access to NFC on the device except for Apple Pay.
I have a lot of android tablets that I bought for testing software. Before I had the iPad I used Amazon Fire tablets pretty seriously (read software docs when doing cardio at the gym, I took my best photo of the last decade w/ a Fire tablet) but all of my Android tablets go unused for so long that I can't count on them being charged when I need them.