How To: Install Apps on Your iPhone Easily, No Hacking Skills Required - Gizmodo
gizmodo.com/291184/how-to-install-apps-on-your-iphone-easily-no-hacking-skills-required
From the page
Saved with the link. Notes from 2007 to 2016 are mostly the page's own words, so this is probably an excerpt.
If you wanted to install third-party native software in your iPhone but you didn't had the necessary technical knowledge or courage, the newly updated iPhone Installer.app will make it so easy that it will be very hard to resist.