what is the latest iOS version I can run on iPad

You do not have an iPad Air, you have a 2012, 4th gen iPad Wifi and Cellular data model.

A 4th gen iPad cannot be upgraded beyond iOS 10.3.3/10.3.4.

A 4th gen iPad is an over 7-year old device, now!

Its internal hardware is too old, underpowered and completely incompatible with any current and future versions of iOS.

Sorry. It is what it is at this very late date.

If you need an iPad that can run the latest and greatest versions of iOS, as well as, the most current apps available, then, you will need to purchase a new iPad from Apple or a discounted, refurbished iPad from Apple’s Refurbished & Clearance section of Apple’s Website.

Best of Luck to You!

10.3.4.

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