IOS 13 upgrade on iPad Air Model Number MD788LL/B

Also, the CPU is underpowered.

The highest iOS version that iPad model can go is iOS 12.5 currently.

Pretty much all of the main internal processing in that over 7-year old iPad Air model is incapable of running all of the new, advanced and internal hardware intensive features of iPadOS.

iPadOS is never going to ever happen for that iPad.

Sorry.

If you need/want an iPad with an up to date iPadOS with access to current, updated apps, then you really need to seriously consider a new iPad model OR a much “newer” , used iPad model capable of running the latest iPadOS versions. There are plenty of newer, older iPad models that can run the latest, current versions of iPadOS.

Sorry & Best of Luck to You!

A first generation iPad Air can only be updated to iOS 12.5.

Apple ended major update support for iPad Air1 in September 2019. Whilst the iPad Air1 has since continued to receive “point” security updates, the Air1 cannot be updated to iPadOS 13 (or any later major versions of iPadOS) as the internal hardware does not meet the minimum technical requirements (CPU or RAM) for newer versions of iOS/iPadOS.

Some App developers have dropped support for iOS versions preceding iOS 13.x for technical reasons (often because APIs or software libraries upon which they rely have been updated in the new version of iPadOS, making their App incompatible with earlier versions). 

Whilst many App titles remain compatible with your iPad Air1, if you want or need to access to Apps requiring the most recent versions of iOS, you’ll need to consider replacement of your iPad with a newer or current model that supports iPadOS14.

Sorry, I appreciate that this may not be what you were hoping to learn.

I hope this information provides helpful clarity as to your available options - and the limitations of your existing iPad Air.

It's a first generation model and doesn't have enough RAM.

(188599)

It's not upgradable. For reference, all of the compatible models have 2GB or more.

(188600)