Certified Android devices won't let users sideload APK app files anymore, or at least it won't be straightforward - CNX Software
… Install apps – You will then be able to install apps from unverified developers, with the option of enabling this feature for 7 days or indefinitely. That’s inconvenient, but at least people won’t need to pay to sideload apps, and developers who prefer to remain anonymous will be able to do so. …