This is the most sensitive part of the discussion. An IPA file is the application bundle for an iOS app. There is no legitimate public archive where you can download every version of every app. However, there are a few theoretical avenues a user might explore, each with significant caveats.
It runs perfectly on older iOS versions (like iOS 9, 10, or 11) where modern apps instantly crash. djay 2 for iphone ipa v281 work
Before diving into the technical side, it's essential to understand the app in question. djay 2 for iPhone is a mobile DJ application developed by the German company Algoriddim. Originally launched in 2013, djay 2 was the successor to the original djay app, which won an Apple Design Award in 2011 for its intuitive and powerful interface. This is the most sensitive part of the discussion