To easily know reputed apps on playstore, many people would have downloaded the app, like 500 thousand to 1 million people would have downloaded such app, this makes it authentic, there will be some that have 1000 downloads, these are the fake ones. But, still, I will not advice anyone to make use of playstore for download, that is why I like your number 2 content.
From OP
2. If you're going to download a cryptocurrency app, make sure you get the link from the company's official website.1. Only install apps from the App Store that have been approved.
If an app is not approved, it won't be on playstore, there a many scam approved apps, some will later be reported before it will be removed. Thanks to Bitcointalk, because there are many we have reported, especially fake Electrum app that was later removed.
3. Never give out sensitive information, such as your wallet private key or password, on any website or application.
Yes, including seed phrase which is the most commonly demanded for by scammers.
4. Always read people's review about the App on playstore first before downloading it.
Do not totally trust reviews, it can help but there are many companies paying people for good review. Just trust forum like Bitcointalk. If you are not sure about an app, just bring it up here for people to review it for you, especially crypto wallets.