Apple:

Starting November 3, 2019, some iPhone and iPad models introduced in 2012 and earlier will require an iOS update to maintain accurate GPS location and keep the correct date and time. This is due to the GPS time rollover issue that began affecting GPS-enabled products from other manufacturers on April 6, 2019. Affected Apple devices are not impacted until November 3, 2019.

By my math, that’d be iPhone 5 or earlier, iPad (4th gen), iPad mini or earlier.