Apple recommends using San Francisco UI Text for IOS 10 in design, but what about the previous axes?

Question

iOS

Apple recommends using San Francisco UI Text for IOS 10 in design, but what about the previous axes? It is not in Xcode, it turns out that it must be built in in all previous axes, will it be the same, or should Helvetica be left for them?
After all, they do not say to completely switch to it, but recommend only to the 10th axis.

Answer 1

If the font is important to you, then of course you will need to download it from the apple website in the develop -> download -> SF UI Font section to use it, but more often developers use systemFont and it substitutes the system font, for ios 9-10 it will be SF. Naturally, no one is forcing you to use only SF, and I would advise you to install a system font, no one will punish you for this, and both fonts are very good.