I've been using AI since pre-ChatGPT so I'm decently familiar with the landscape. I've used Voila daily for hundreds of days. When it first hit AppSumo, it was solid. I'm not sure if the other reviewers haven't used ChatGPT, Perplexity, Gemini, or other tools, but Voila is now WAY behind. The mobile app (which is basically just a paired down wrapper) hasn't been updated since the release date. Chat history is inconsistent on all platforms (and doesn't sync). Only two models (4o and 4o-mini) are supported. The macOS desktop app has a bunch of bugs related to the settings.
The main pro is that it's a LTD here. But I still find TripleO more useful, with unique features, and actively developed.
In my opinion, ChatGPT does everything Voila does, only better. For web search/citations, go Perplexity free version. If you're a power user of AI, you'll certainly want that over this.
I'll update this review if Voila pushes some big improvements, but right now i just use it when I don't want something going into my ChatGPT memory.