What does “This method is deprecated” mean for application developers

Question

I see quite a few good old useful methods or even entire classes being \"deprecated and obsolete\".

But code that used to call those methods continues to work. So,

Answer 1

Even when they are deprecated, they may compile but not work. Google has decided to delete various functionality at the low OS level.

Case in point. Google, at android release 2.3 deprecated many but not all method API's that allowed call recording. They compile OK but do not function since Android 2.3 and forward on any android phone device, or tablet with phone capabilities.