Having been through multiple iPhones, iPads as well as multiple Android (Samsung, Sony & Huawei) phones & tablets I have found the iOS system far more user friendly, intuitive and sensible to use/operate. Plus the regular updates from Apple, as opposed to Android (I'm still waiting for Huawei to release any OS or security updates for a 3 year old P8......).
Been using an iPhone from iPhone 5 when I got the *****s with Blackberry who refused to repair a 3 month old unit that was fubar. Subsequently had 5S and now using 6S. Was due for an upgrade 3rd quarter last year, decided no need, phone still works 100% all the time.
I know there are lots of Apple detractors, however if you want to use the phone as a work tool & require it to simply work, then IMHO Apple is the only way to go.
If on the other hand you want it as a toy to fiddle and play with, then go Android as it is easier to flash a new ROM and faff with.
Couple of reasons to illustrate why I feel the way I do:
1. When replying to an email from iOS there is the option to always BCC myself. This way the email chain remains intact on both desktop & phone. This can be set to happen automatically. On Android I need to input my own address in the BCC field every time I send an email. At 40+ emails a day it becomes a PITA.
2. When deleting a text message on iOS I simply swipe left. On Android I must touch & hold, then press delete, then press OK when asked if I am sure I want to delete it. What a PITA. Is this OS for stupid and/or indecisive people?

3. iOS keyboard is brilliant. Plus it has emoticons etc. built in already. Android (both Sony & Huawei) stock keyboard is atrocious! I then need to go to the App store, seek & find an app for something as basic as a keyboard? Seriously? It's idiotic, why can't the standard ones be functional? Huawei didn't even have emoticons! So I had to try 3, 4 or 5 apps before finding a decent one, just to be able to bloody type an email or text message!
Currently using a P8 and the 6S. Hate the P8 - slow, lags, glitches on emails at least once a day & needs to be rebooted. It will be upgraded in a few months to an iPhone X.