Android has plenty of its own problems, but not so much in this category. Android users can set default browser, email, SMS app, etc., where iOS does not allow this. Any navigation app can work while the device is locked, it's enabled by a permission called "Draw over other apps", IIRC.
In my opinion, the problem with Android is not that you can't add to its functionality, which you can, but that you can't effectively limit Google's privacy-invasive functionality (much worse than iOS's) unless you can unlock the bootloader.
In my opinion, the problem with Android is not that you can't add to its functionality, which you can, but that you can't effectively limit Google's privacy-invasive functionality (much worse than iOS's) unless you can unlock the bootloader.