So I have the 2014 PHB, went through purchasing that. I am not interested in getting the 2024, my DM wants nothing to do with it and I honestly feel the characters are too OP, granted that is my opinion. However when I open the 2014 PHB it keeps saying to Update it. I am concerned that if I do that I will lose functionality with what I have, so I am so far opting out and just opening. Is there a description of what I gain or lose by updating, that way I can make that decision? Otherwise, the answer is no, and how do I make it stop asking?

The 2024 Free Rules and Player's Handbook are different books from the 2014 Player's Handbook. Whatever is being updated in the app, it's probably fixes for typos, formatting, or links.

Yes. 

it is formatting and minor changings -- not a content change.

Thank you 

Look at it this way: do you think they’re just going to hand you their new $40 product in an update?

To be fair the 2024 Free Rules exist, which I think is where the anxiety was coming from.

I'm actually more concerned they're going to remove more than add.

Quote from izgerry >>

I'm actually more concerned they're going to remove more than add.

 They can do that without you updating unless you put the books on it and then turn off the device's internet. You can test this even. Hop into a campaign with someone and download a book you don't have. Then remove yourself from that campaign. When the app connects to the internet, your access to the unowned book will be taken away.

This worry is pretty baseless. WotC has no spine. Look how they groveled when they tried to swap the 2014 spells and magic items for the 2024 versions. This is just from a handful of spells and magic items. The removal of whole books would be an even greater controversy.

OK, fair point. Just wanted to make sure it's "safe" to update then.