There are quite a few possible methods by which a user can do this. Firstly, the user will need to visit the settings portion of their device. Once the user is in there, they will have to find the folder called security and privacy and then follow the path by visiting more settings. They will have to press the option that helps them download applications from external places to their phones. Once sanctioned, they can go to any internet browser, like Google Chrome and even Mozilla Firefox. They must download the files for the App they desire to be kept on their device. If the user has done this successfully, they may toggle the place that allows such application installation and turn it on. The above method should work very efficiently on phones that have androids of 8 and above.