On BB10 BlackBerry World, Facebook, Messenger, WhatsApp, Gmail, web browsing and countless other apps worked just fine without having to subscribe to BIS. You are correct about BB’s proprietary email and messaging service, but I never used them anyway. You didn’t have to, unlike pre-BB10.BlackBerry Internet services known as BIS will be closing on 31st October 2019 for Consumer and 15th November 2019 for Small Business and Corporate customers, so you won’t be able to use the following applications with your BlackBerry device: BlackBerry Messenger, BlackBerry World, BlackBerry Email, Facebook and web browsing. You'll still be able to use your phone to make and receive calls, send and receive texts, and may be able to use data through a WiFi connection or your data plan allowance. https://community.ee.co.uk/t5/Texti...et-Services-BIS-closure-affect-me/td-p/809938
Anyway, BB10 is dead and useless now anyway, unfortunately. That’s why I was forced to ditch my BlackBerry Passport and get an iPhone X (tried a couple of the ‘BlackBerry’ Android phones in between, but they were crap).