I'm using a BB Z10 and a Jolla ...

as it comes to Android apps there are apps that won't run on the Jolla and apps that won't run on the BB

On the BB it works quite good with the Amazon store - but if you bought apps from Google you'll have to buy them again :-( - you can load paid-apps from the Play Store with Snap (you have to buy them with your browser!) but not every paid app is working and in-app-purchases don't work in most cases! All the apps that net the google-play-services won't work (or need patching - have a look at crackberrry forums)

On the Jolla more of the apps (I tried) are working (you can install Play Store and services if you like, so you can purchase apps directly - but be aware that you'll have some google on your device if you do that) but it seems as the Jolla is recognized as a rooted device, so some apps can't be installed (many banking apps for example)

So it definitely depends on your needs which Android runtime is better for you ...

Here you can find a list of working Android apps (an issues) for BlackBerry 10 (it's german but that should not be a problem as the names of the apps are international ;-) )

For Android apps on the Jolla search at TMO ;-)