Any older iPads, like the iPad Air 2 and iPad Mini 4 and earlier iPad models CANNOT use the any Apple Pencils.
Sorry.
You will need to seek out a third party alternative smart Bluetooth stylii.
The ONLY third party, smart Bluetooth stylus that I can, honestly, recommend that actually works well with ANY iPad model is the Adonit Pixel.
http://www.adonit.net/jot/pixel/
This smart, Bluetooth stylus works across a wide range of iDevices.
The Bluetooth connection is stable and its Bluetooth pressure sensing technology is very smooth, natural feeling and has consistent line drawing ability.
Plus it's a quality made, aluminum stylus with two programmable buttons.
I have been using this stylus for nearly 3 years now and it is really good on my iPad.
The Adonit Pixel works with iPads all the way back to the 2012, 1st gen iPad Mini and iPad 4th generation!
Has ON/OFF/app shortcut buttons.
Has a nice fine, textured pen tip AND a nice rubber grip.
Magnetically charges, has an auto 15 minute shutdown feature ( to preserve battery life ), charges in a hour.
Has both a small USB charger that that plugs into any USB charging block OR you can purchase an optional charging dock.
I find it only lasts for anywhere between 9-12 hours, but Adonit claims up to 16 hours of continuous use on a charge cycle.
Made of very high quality aluminum materials.
Works with about a dozen of the major/popular drawing/sketching/painting apps (the Pixel/Pixel Pro works with, but currently not “officially” supported with Procreate, but it still works and works pretty well in Procreate ), and about a half dozen of the popular note taking apps, a half dozen writing apps and about a half dozen PDF style/compatible apps.
You WILL have to perform some pairing and setup parameters in each of the Adonit Pixel compatible apps.
You just DO NOT simply turn on Bluetooth on an iDevice and turn on the Adonit stylus and expect to start writing.
The Adonit Pixel stylus is NOT an Apple Pencil in this regard/respect.
You have to initially Bluetooth pair the Adonit Pixel, setup the hand/palm position and in many apps, set up the stylus screen pressure sensitivity for each and every compatible app!
Once you have, initially, done all of this, all Adonit Pixel compatible apps will remember these settings for future use!
Some Adonit Pixel users claimed their stylus doesn’t work, but it does work well IF you properly know how to set up the Adonit Pixel/Pixel Pro!
Here’s my “up to date”, comprehensive, but still incomplete, list of Adonit Pixel/Pixel Pro compatible apps for the iPad/iPad Pro.
All apps listed support pressure sensing and palm rejection.
Compatible Adonit Pixel apps for drawing
Animation Desk
Amaziograph
Adobe Photoshop Sketch ( palm rejection ONLY, No pressure, no sensing line weight or opacity variations )
ArtRage
Art Studio Pro ( fully supports the Adonit Pixel and is just as great as Procreate on the iPad )
AutoDesk SketchBook
Colored Pencil
Comic Draw
Concepts
Interactive SketchBook
Inkist
Medibang Paint
ProCreate ( palm rejection improved using special, non-electrical conducting, lycra-based material drawing glove )
Pixelmator ( new versions, now, STILL support the Adonit Pixel, but it is now listed in the active stylus settings as “unsupported stylus”. The Pixel STILL works as it should in this app, though )
Tayasui Sketches/Sketches Pro ( the new, free Tayasui Sketches School version works with this stylus, but without any palm rejection or pressure sensing, so you need to use a special, non-electrical conducting drawing glove with the Sketches School version to lay your hand/palm down on the iPad’s screen )
Vectornator
ZenBrush 1 & 2
Compatible Adonit Pixel apps for Notes and Notes with drawing types of apps.
GoodNotes 4 & 5
Notability ( palm rejection noticeably improved using special, non-electrical conducting, lycra-based material drawing glove )
Note Shelf 1 & 2
Notes Plus
Notes Writer
QuickNotes X Pro
uPad
Zoom Notes
PDF Expert
PDF Pen
Foxit PDF
If interested, to make sure you get the latest installed stylus firmware, you must order one of these directly from the Adonit website.
This stylus works with other non-compatible apps, too, but without any palm rejection and/or pressure features.
You can use this stylus with other apps but will not be able to lay your palm on the screen, unless you use special, non-electrical conducting, lycra-based material drawing glove that works by isolating your hand/palm and allow you to lay your hand/palm on the screen as you draw in these non-compatible Adonit stylus apps.
Something like this.
https://www.amazon.com/Professional-Anti-fouling-Drawing-Tablet-Graphic-Right-Ha nd-Left-Hand/dp/B017R8M2JY/ref=sr_1_1_sspa?ie=UTF8&qid=1543548123&sr=8-1-spons&k eywords=lycra+drawing+gloves&psc=1
Good Luck to You!