I want to use my old iPhone 4S as a "software token machine", so I installed and configured all the needed apps in there (and just those ones). It is running iOS v9.3.6.
One app, at its latest version, is refusing to install (SafeNet MobilePass) because my phone doesn't run iOS v10.
Before ditching definitely my plan, is there a way to install an older app version without jailbreaking?
P.S. I only have Linux PCs as it looks like a PC could be needed.