To standardize type across your designs, you'll want to establish a system of fonts, with specific sizes and line heights. Generally speaking, your standards will need to capture everything from large display typography for headlines, to smaller sizes for body copy. You'll need enough variety to support all of these use cases, but not so many options that designers don't know when to use which styles.
A lot of factors go into the decision of which fonts to use in your system. You should consider things like:
- App performance: Do you have a performance budget? How many fonts do you need to load? Will you leverage fonts that are already-installed on different platforms?
- Personality: Do you have established brand fonts as part of your company's visual identity that makes sense to use?
- Multiple systems: Decide if it makes sense to have one unifying type system or different strategies for different use cases: for instance in-product vs. marketing website (where brand-personality may carry more weight).
- Pairings: Can you get all of the typographic range you need in your system from one font family? Consider pairing typefaces. You can reserve more decorative fonts for large-sized text that you use sparingly, and keep legible typefaces for body copy. If you're using free Google fonts, we also have created a resource to help you easily explore a variety of possibilities with these pairing palettes.