How do I download latest compatible version of an app? So, I was trying to download PicsArt and it says that I need a 10.0 IOS version. And that's happenning to almost every awesome app and games in the App Store. And that's the problem, I almost can't download anymore because of that. Now, let's go to the question, How do I download the latest compatible version of an app that I haven't purchased before?

Please answer because I'm trying to download not just PicsArt but many more...
You need to update your iOS version, if possible, or live without those apps.  

As of iOS 11, Apple has told developers they must update their apps to 64-bit.  Older, 32-bit, apps can't be on the App Store anymore.

If you're on any version older than iOS 11 and the developer hasn't updated their app (it's the developer's responsibility to do this, not Apple's), you will not be able to download or run the app.