I am the owner of an IPhone 7 plus. Currently my software update is IOS 12.1 Because I updated to the version 12, I lost the capability of one of my favorite Apps, which I subsequently deleted. The App company- GLU, rendered the App inoperable if you updated the the version 12. There are app players out there who kept the version at 11.9? and can still use the app which I still would like to do. 2 questions. While still maintaining my current phone 7plus, can I somehow return to a prior software version prior to 12? and second, could I then recover the deleted app to see if it still functions? Is all of this possible? thanks, george