eBay sent an email blast out to eBay account users many months ago warning users that they would be retiring support and operation of their older app under iOS 10, just like they did when they discontinued support for their older app for iOS 9 users about a year, ago, or so.
No matter, now.
These old iPad 2, 3, 4 and 1st gen iPad Mini models are, virtually, 8 and 9-years old, now.
The amount of older, compatible, available apps for these old iPad models has dwindled significantly since the beginning of 2020!
Getting older versions of apps for these old iPad models, initially from Apple’s iOS App Store is getting very difficult and very problematic and this issue is getting, painfully, much worse, now, in 2020!
As of the beginning of 2019, many, MANY third party app developers are all more quickly and completely permanently dropping AND removing older app support for all old 7, 8 and 9-year iPads that are running 2-3 year old and earlier iOS versions ( iOS 10 and earlier ).
Third party app developers are removing all of their older, legacy versions of their apps from Apple's App Store servers, now.
Third party app developers no longer want to support these 8 and 9-year old or older iOS devices, any longer!
Older versions of apps are, soon, going to be gone for good, now!
These old iPads are now reaching their complete end of life and support cycles.
So finding older versions apps for older iPads, while still possible, currently, will be a very tough challenge, now, in 2020.
Old iPads that can no longer be upgraded/updated will have NO MORE APPS AVAILABLE for initial download, at all, soon, from the Apple iOS App Store, for such old iOS devices in the very near future.
Older versions of apps for these older iPads will be completely gone, at some point, in the very foreseeable future.
Old 8 and 9-year old iPads will be pretty much obsolete by the end of the 2020 year!
Again, it is what it is, today, in the year 2020!
You will never get any more older versions of popular apps for these old iPads, any longer.
The apps that these old iPads already have on them, and still work, will be the apps these iPads will be stuck with!
Basically, these old iPad models are just good for FaceTime and somewhat limited Web browsing via some other, more up to date third party Web browsers and NOT using that nearly 4-year old iOS Safari Web browser.
This is the harsh reality for these 8 and 9-year old, OR OLDER, iOS devices, now!
So, this is REALLY NOW the time to seriously consider a new or discounted, refurbished iPad from Apple or other Apple authorised resellers.
A lot has happened with iPad and iOS in 7-9 years and in the past 2 to 3-1/2 years since iOS 9 and 10.
Sorry & Best of Luck to You!