Yarn usage adds complexity as it needs to be separately installed. Since version 5 of NPM (which comes installed with node) yarn (as far as I know) offers nothing of interest. For the sake of simplicity, NPM should be preferred.
Each should be prioritised and changelog checked to see if security updates are present, breaking changes, what bugs have been fixed, performance improvements, etc.
Yarn usage adds complexity as it needs to be separately installed. Since version 5 of NPM (which comes installed with node) yarn (as far as I know) offers nothing of interest. For the sake of simplicity, NPM should be preferred.
Outdated packages lis follows, more information:: https://docs.npmjs.com/cli/outdated
Each should be prioritised and changelog checked to see if security updates are present, breaking changes, what bugs have been fixed, performance improvements, etc.