There are G-meters...but only for the iOS 13.5 or later.
https://apps.apple.com/us/app/g-meter/id1516294953
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There are third-party offline map apps...but only for the iOS 14.0 or later.
https://apps.apple.com/us/app/maps-me-offline-maps-gps-nav/id510623322
There are official offline Apple Maps...but only for iOS 17 or later.
https://support.apple.com/en-us/105084
There are offline GIS(geographical information system) maps to use in the stix.
https://doc.arcgis.com/en/field-maps/ios/use-maps/download-maps.htm
There is some nonsense about pairing it to a computer or whatnot.
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Have to ask the question, but what is it about pre-13.5iOS hardware...that can't handle OBD2 or maps?