What's a Lion to do??
Install the latest compatible version of an app on an earlier version of iOS or OS X - Apple Support
According to the above article, if an App requires a newer version of OS X, the App Store will help you install the last compatible version on an older version of OS X if you previously purchased the App. This feature was introduced in the App store on OS X 10.8 and later.
So those of us running OS X 10.6 Snow Leopard and OS X 10.7 Lion have the App Store but not this "Last Compatible" feature. And most of the good Apps that are continually developed and supported are listed as requiring OS X 10.8, 10.9 or even higher.
If Apple won't support our hardware for upgrading the OS (I have a 64-bit Intel Core 2 Duo MacBook that cannot go beyond Lion), how are we supposed to purchase and/or install any Apps? Most of these incompatible Apps have older versions that WERE compatible with Lion and Snow Leopard. How do I get them? Does Apple seriously expect its users to pursue each individual developer to see if they have some mechanism in place to download older versions of their apps and a spreadsheet to say which app is compatible with which OS?
For example, even mainstream developers like AutoDesk don't provide me a way to download the older versions of AutoDesk Sketchbook Express that were and still are compatible with OS X Lion. The latest version requires at least OS X 10.8. They - and most developers - probably think Apple is handling version control per the above article.
What's a Lion to do?
MacBook, Mac OS X (10.7.5)