Primal has a lot of great upsides and a lot of downsides to go with them. Everything is tradeoffs.
I wrote a full review of Primal for Android on my site www.nostr-reviews.com that goes over many of these tradeoffs in detail.
There are two inexcusable problems I have with Primal that they have said they are working on fixing, and then I will be reconsidering the overall score I gave them:
1. They still only allow users to login by pasting their private key into the app. They need to add support for Android signers like Amber and remote signers like Amber or nsec.app.
2. They still only support a deprecated spec for DMs that leaks metadata about the sender and receiver. They need to upgrade to the latest DM spec for the sake of user privacy.
There are other issues, but those are the biggest ones for me.