I don't have many QOL apps.

I like Pixelmator. Photoshop is way to expensive and Pixelmator is both affordable and feature rich.

I also have Alfred set up so I can monitor what's going on outside. Doesn't always work well for me, but the phones I use for cameras are really old.

Aside from that I have quite a few web browsers I use to test my apps.

I mostly use BBEdit and Fetch, and those are about the only apps I pay to keep updated, but that's pretty rare.

I will take a look at the apps "is_taken" has listed here though.